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2026 Vol. 56, No. 4
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2026, 56(4): 1-9.
doi: 10.3724/j.gyjzG25032402
Abstract:
Based on the practical background of urban stock renewal and quality enhancement， this paper focuses on the urban university campus， and proposes a vision of symbiotic and integrated development between the campus and the city， and aims to selectively adopt planning and evaluation follow-up methods to enhance the scientificity and inclusivity in addressing complex urban challenges. On the basis of analysis and research， a comprehensive five-dimensional conceptual renewal planning guideline was developed. Taking the front area of the Dongfeng Road Campus of Guangdong University of Technology as an example， starting from the five dimensions of campus space structure， functional connotation， texture and form， external space， and existing buildings， renewal planning strategies and a work effectiveness evaluation system were constructed. A renewal plan for both the campus front area and the existing individual structures was formed to provide a reference for the renewal concept， working mode， and specific strategies in school-city symbiosis zones of urban universities.
Based on the practical background of urban stock renewal and quality enhancement， this paper focuses on the urban university campus， and proposes a vision of symbiotic and integrated development between the campus and the city， and aims to selectively adopt planning and evaluation follow-up methods to enhance the scientificity and inclusivity in addressing complex urban challenges. On the basis of analysis and research， a comprehensive five-dimensional conceptual renewal planning guideline was developed. Taking the front area of the Dongfeng Road Campus of Guangdong University of Technology as an example， starting from the five dimensions of campus space structure， functional connotation， texture and form， external space， and existing buildings， renewal planning strategies and a work effectiveness evaluation system were constructed. A renewal plan for both the campus front area and the existing individual structures was formed to provide a reference for the renewal concept， working mode， and specific strategies in school-city symbiosis zones of urban universities.
2026, 56(4): 10-16.
doi: 10.3724/j.gyjzG24051701
Abstract:
In the context of high-tech manufacturing， new industrial buildings are required not only to meet production and equipment needs， but also to enhance spatial quality， cultural expression， and human-centered experience. Using Zhejiang Wedu Medical Device Manufacturing Park as a case， architectural narrative in new industrial building design was examined. Based on the relationship among people， factory， and environment， the design developed a narrative strategy centered on path， scene， and culture. Integrating function， landscape， and cultural expression， it strengthened people-space interaction and built a closer connection between architecture and the site’s natural landscape. The project provides a reference for related design practice.
In the context of high-tech manufacturing， new industrial buildings are required not only to meet production and equipment needs， but also to enhance spatial quality， cultural expression， and human-centered experience. Using Zhejiang Wedu Medical Device Manufacturing Park as a case， architectural narrative in new industrial building design was examined. Based on the relationship among people， factory， and environment， the design developed a narrative strategy centered on path， scene， and culture. Integrating function， landscape， and cultural expression， it strengthened people-space interaction and built a closer connection between architecture and the site’s natural landscape. The project provides a reference for related design practice.
2026, 56(4): 17-21.
doi: 10.3724/j.gyjzG23101007
Abstract:
For the problem of exceeding the tensile force limit of large-span mesh shell structural members with bolted ball nodes， a new spatial mesh shell structural form was proposed， and the new mesh shell structure was analyzed in comparison with the quadrangular cone mesh shell structure to explore the superiority of the structure. The parameters of the structure， such as side-to-side ratio， mesh shell thickness， mesh size， and so on， were analyzed in several cases. The change rule of structural strength， steel consumption， and other indexes with the above parameters was obtained. The study shows that the new space mesh shell structure form can significantly reduce the tension of the lower chord member， meet the strength requirements of the bolted ball node， and broaden the span range of the bolted ball node.
For the problem of exceeding the tensile force limit of large-span mesh shell structural members with bolted ball nodes， a new spatial mesh shell structural form was proposed， and the new mesh shell structure was analyzed in comparison with the quadrangular cone mesh shell structure to explore the superiority of the structure. The parameters of the structure， such as side-to-side ratio， mesh shell thickness， mesh size， and so on， were analyzed in several cases. The change rule of structural strength， steel consumption， and other indexes with the above parameters was obtained. The study shows that the new space mesh shell structure form can significantly reduce the tension of the lower chord member， meet the strength requirements of the bolted ball node， and broaden the span range of the bolted ball node.
2026, 56(4): 22-30.
doi: 10.3724/j.gyjzG23052206
Abstract:
By conducting wind tunnel pressure measurement test based on a rigid model of a long-span cantilevered roof， the estimation of non-Gaussian extreme wind pressure on the roof surface and the prediction of peak factors were studied. The time series of wind pressure on the roof surface was obtained through experiments， and the distribution characteristics of the mean wind pressure coefficient， fluctuating wind pressure coefficient， skewness， and kurtosis on the roof surface were analyzed under typical wind directions of 0 °， 45 °， and 90 °. The Gaussian peak factor method and the revised Hermite series method were used to calculate the peak factor at typical measuring points， respectively. The non-Gaussian characteristics and wind pressure fitting at typical measuring points were evaluated based on five probability density functions， and the minimum wind pressure estimation was obtained using the revised Hermite series method and the existing extreme wind pressure evaluation method， respectively. Finally， the peak factor was predicted using a general regression neural network. The results showed that the minimum wind pressure on the roof surface was significant under typical wind directions of 0°， 45°， and 90°， and the long tail of the wind pressure distribution was measured in the negative direction； the Gaussian peak factor method was found to frequently underestimate the peak factor of non-Gaussian wind pressure； the revised Hermite series method estimated the peak factor more accurately and performed best in wind pressure fitting， especially in the negative pressure long tail section； the revised Hermite series method obtained better minimum estimates； the general regression neural network based on the fourth-order statistics of wind pressure time history exhibited good prediction performance.
By conducting wind tunnel pressure measurement test based on a rigid model of a long-span cantilevered roof， the estimation of non-Gaussian extreme wind pressure on the roof surface and the prediction of peak factors were studied. The time series of wind pressure on the roof surface was obtained through experiments， and the distribution characteristics of the mean wind pressure coefficient， fluctuating wind pressure coefficient， skewness， and kurtosis on the roof surface were analyzed under typical wind directions of 0 °， 45 °， and 90 °. The Gaussian peak factor method and the revised Hermite series method were used to calculate the peak factor at typical measuring points， respectively. The non-Gaussian characteristics and wind pressure fitting at typical measuring points were evaluated based on five probability density functions， and the minimum wind pressure estimation was obtained using the revised Hermite series method and the existing extreme wind pressure evaluation method， respectively. Finally， the peak factor was predicted using a general regression neural network. The results showed that the minimum wind pressure on the roof surface was significant under typical wind directions of 0°， 45°， and 90°， and the long tail of the wind pressure distribution was measured in the negative direction； the Gaussian peak factor method was found to frequently underestimate the peak factor of non-Gaussian wind pressure； the revised Hermite series method estimated the peak factor more accurately and performed best in wind pressure fitting， especially in the negative pressure long tail section； the revised Hermite series method obtained better minimum estimates； the general regression neural network based on the fourth-order statistics of wind pressure time history exhibited good prediction performance.
2026, 56(4): 31-41.
doi: 10.3724/j.gyjzG24012607
Abstract:
A novel floor system called one-way flat top-chord-free open-web truss composite floor is proposed in this paper. This system innovatively removes the steel top chords and diagonal web members of a conventional steel truss composite floor and uses mound blocks as vertical webs， which are connected to the steel bottom chords and the concrete slabs with studs. By adopting the assumption of mound block continuum， differential equations were established and solved. Under the condition of two-point loading， the internal forces， ultimate bearing capacities， and the elastic deformation formulas were obtained and verified by experimental data. Parametric analysis of elastic deflection was also conducted. The results showed that the ultimate bearing capacity of this floor system could not be determined by the conventional method for composite beams， which relies on the bearing capacity of a single cross-section. Instead， various failure modes and corresponding bearing capacities of different components should be considered. The deflection calculation formula derived in this paper could accurately calculate the elastic deformation of the composite floor system.
A novel floor system called one-way flat top-chord-free open-web truss composite floor is proposed in this paper. This system innovatively removes the steel top chords and diagonal web members of a conventional steel truss composite floor and uses mound blocks as vertical webs， which are connected to the steel bottom chords and the concrete slabs with studs. By adopting the assumption of mound block continuum， differential equations were established and solved. Under the condition of two-point loading， the internal forces， ultimate bearing capacities， and the elastic deformation formulas were obtained and verified by experimental data. Parametric analysis of elastic deflection was also conducted. The results showed that the ultimate bearing capacity of this floor system could not be determined by the conventional method for composite beams， which relies on the bearing capacity of a single cross-section. Instead， various failure modes and corresponding bearing capacities of different components should be considered. The deflection calculation formula derived in this paper could accurately calculate the elastic deformation of the composite floor system.
2026, 56(4): 42-50.
doi: 10.3724/j.gyjzG23101614
Abstract:
The temperature effect of solar radiation on a large-span metal roofing system under insolation is very significant. In this paper， the temperature field of the roof panel and its changing law were studied by taking a vertical locking seam aluminium alloy roof as the object. Considering the influence of different horizontal inclination angles and panel orientation on the temperature of the roof panel， ANSYS thermal analysis module was used for upright lock seam roof system roof panel to establish a finite element model considering the air convection heat transfer， ambient long-wave radiation heat transfer， solar radiation and other factors， analysed the roof of the various positions in the solar irradiation of the temperature distribution law. At the same time， to carry out tests to verify the results of numerical simulation， according to the test results， a detailed analysis of the temperature field and the change rule of the roof panel under natural environmental conditions， the test results verify the feasibility of the simulation method. The results show that the aluminium alloy roof panel is a heat-sensitive component， in the sunshine under the action of a very short period of time rapid warming， no solar radiation when the roof temperature drops rapidly， the sun direct radiation is the main influence of the temperature rise， the same moment the roof temperature field tends to be consistent distribution is more uniform. The maximum temperature of the roof panel reaches 66.93 ℃， and the temperature difference with the environment reaches 33.93 ℃. It will be more obvious in the actual large-span aluminium alloy roofing system.
The temperature effect of solar radiation on a large-span metal roofing system under insolation is very significant. In this paper， the temperature field of the roof panel and its changing law were studied by taking a vertical locking seam aluminium alloy roof as the object. Considering the influence of different horizontal inclination angles and panel orientation on the temperature of the roof panel， ANSYS thermal analysis module was used for upright lock seam roof system roof panel to establish a finite element model considering the air convection heat transfer， ambient long-wave radiation heat transfer， solar radiation and other factors， analysed the roof of the various positions in the solar irradiation of the temperature distribution law. At the same time， to carry out tests to verify the results of numerical simulation， according to the test results， a detailed analysis of the temperature field and the change rule of the roof panel under natural environmental conditions， the test results verify the feasibility of the simulation method. The results show that the aluminium alloy roof panel is a heat-sensitive component， in the sunshine under the action of a very short period of time rapid warming， no solar radiation when the roof temperature drops rapidly， the sun direct radiation is the main influence of the temperature rise， the same moment the roof temperature field tends to be consistent distribution is more uniform. The maximum temperature of the roof panel reaches 66.93 ℃， and the temperature difference with the environment reaches 33.93 ℃. It will be more obvious in the actual large-span aluminium alloy roofing system.
2026, 56(4): 51-62.
doi: 10.3724/j.gyjzG23121816
Abstract:
As a common building structure， metal roofs have been widely used in various large public buildings because of their unique advantages such as beautiful shape， light weight and high strength. However， there are still some limitations in the current research on the wind resistance of metal roofing. Therefore， this paper studies the wind resistance of large metal roofing under wind load based on wind tunnel tests on the background of the metal roofing project of Xiamen New International Expo Center. Through the wind tunnel testing， the stress state of the metal roofing under different wind speeds and wind angles was simulated. The distribution of force characteristics， equivalent wind load， and wind vibration coefficient were measured. The standard value of wind load of the envelope structure was obtained， and the two common calculation methods were compared. The envelope results of the two methods are safe in the calculation of the standard wind load of the envelope structure. Finally， the ANSYS finite element software was used to establish the metal roof model of the landside exhibition hall， and the wind vibration calculation was carried out. By analyzing the displacement time history and the equivalent wind load of typical joints， the overall wind load value which could be used in this project design was obtained. The stress characteristics and instability modes of metal roofing in a strong wind environment were summarized， and the factors affecting the wind resistance of metal roofing were analyzed. The strengthening measures for wind resistance design of metal roofing were put forward， including enhancing wind resistance connection and locking height， rational selection of materials and structures， so as to provide a certain theoretical guidance and scientific basis for the design of such structures in the future.
As a common building structure， metal roofs have been widely used in various large public buildings because of their unique advantages such as beautiful shape， light weight and high strength. However， there are still some limitations in the current research on the wind resistance of metal roofing. Therefore， this paper studies the wind resistance of large metal roofing under wind load based on wind tunnel tests on the background of the metal roofing project of Xiamen New International Expo Center. Through the wind tunnel testing， the stress state of the metal roofing under different wind speeds and wind angles was simulated. The distribution of force characteristics， equivalent wind load， and wind vibration coefficient were measured. The standard value of wind load of the envelope structure was obtained， and the two common calculation methods were compared. The envelope results of the two methods are safe in the calculation of the standard wind load of the envelope structure. Finally， the ANSYS finite element software was used to establish the metal roof model of the landside exhibition hall， and the wind vibration calculation was carried out. By analyzing the displacement time history and the equivalent wind load of typical joints， the overall wind load value which could be used in this project design was obtained. The stress characteristics and instability modes of metal roofing in a strong wind environment were summarized， and the factors affecting the wind resistance of metal roofing were analyzed. The strengthening measures for wind resistance design of metal roofing were put forward， including enhancing wind resistance connection and locking height， rational selection of materials and structures， so as to provide a certain theoretical guidance and scientific basis for the design of such structures in the future.
2026, 56(4): 63-69.
doi: 10.3724/j.gyjzG23102204
Abstract:
Standing seam metal roof photovoltaic systems have been widely used in steel structures due to their lightweight and high-strength properties， environmental friendliness， cost-effectiveness， and aesthetic appeal. However， the lack of corresponding design and construction standards has posed challenges in practical applications. Based on a case study of a standing seam metal roof photovoltaic system project project， experimental research was conducted to investigate its wind resistance， watertightness， and air permeability. The results showed that when the test wind pressure was within 3.5 kPa， no residual deformation occurred in the photovoltaic panels， metal plates， fixtures， or supports of the standing seam metal roof photovoltaic system. However， when the test wind pressure was increased to 4.2 kPa and maintained for 23 seconds， the photovoltaic panel detached from the edge photovoltaic fixture， resulting in test failed. The wind uplift resistance test results of the system was thus determined to be at the 3.5 kPa level. The actual wind uplift resistance of the entire system can meet the design requirements and possesses a certain degree of safety redundancy. Both watertightness and airtightness have achieved the highest grades specified in the Test Method of Air Permeability， Watertightness， Wind Load Resistance Performance for Curtain Walls （GB/T 15227-2019）， namely Grade 4 and Grade 5， respectively. The test results meet the design requirements.
Standing seam metal roof photovoltaic systems have been widely used in steel structures due to their lightweight and high-strength properties， environmental friendliness， cost-effectiveness， and aesthetic appeal. However， the lack of corresponding design and construction standards has posed challenges in practical applications. Based on a case study of a standing seam metal roof photovoltaic system project project， experimental research was conducted to investigate its wind resistance， watertightness， and air permeability. The results showed that when the test wind pressure was within 3.5 kPa， no residual deformation occurred in the photovoltaic panels， metal plates， fixtures， or supports of the standing seam metal roof photovoltaic system. However， when the test wind pressure was increased to 4.2 kPa and maintained for 23 seconds， the photovoltaic panel detached from the edge photovoltaic fixture， resulting in test failed. The wind uplift resistance test results of the system was thus determined to be at the 3.5 kPa level. The actual wind uplift resistance of the entire system can meet the design requirements and possesses a certain degree of safety redundancy. Both watertightness and airtightness have achieved the highest grades specified in the Test Method of Air Permeability， Watertightness， Wind Load Resistance Performance for Curtain Walls （GB/T 15227-2019）， namely Grade 4 and Grade 5， respectively. The test results meet the design requirements.
2026, 56(4): 70-81.
doi: 10.3724/j.gyjzG23111205
Abstract:
In previously reported experimental studies on T-head square-neck one-sided bolted （TSOB） beam-to-square hollow section （SHS） column joints， bolt pull-out failure caused by the bulge deformation of the column wall has been identified as a typical failure mode. To prevent SHS wall deformation under the bending moment at the beam ends and to improve the deformation capacity of the joint， this paper proposes assembled H-steel strengthening measures for beam-column joints. Monotonic static load tests were conducted on four joints with H-steel components to explore the influence of the length and plate thickness of the strengthening components on the structural response of the joints. The test results showed that the H-steel components prevented bolt pull-out failure and increased the yield and peak bending moments of the joints by 69.3%-72.6% and 22.5%-39.4%， respectively. It is recommended that TSOB beam-to-SHS column joints use extended H-steel components， the cross-section of which should be designed according to the internal force of the joint.
In previously reported experimental studies on T-head square-neck one-sided bolted （TSOB） beam-to-square hollow section （SHS） column joints， bolt pull-out failure caused by the bulge deformation of the column wall has been identified as a typical failure mode. To prevent SHS wall deformation under the bending moment at the beam ends and to improve the deformation capacity of the joint， this paper proposes assembled H-steel strengthening measures for beam-column joints. Monotonic static load tests were conducted on four joints with H-steel components to explore the influence of the length and plate thickness of the strengthening components on the structural response of the joints. The test results showed that the H-steel components prevented bolt pull-out failure and increased the yield and peak bending moments of the joints by 69.3%-72.6% and 22.5%-39.4%， respectively. It is recommended that TSOB beam-to-SHS column joints use extended H-steel components， the cross-section of which should be designed according to the internal force of the joint.
2026, 56(4): 82-93.
doi: 10.3724/j.gyjzG24022309
Abstract:
Aiming to address the problems of low lateral stiffness and difficult replacement in traditional flanged joints， a steel frame joint with a dumbbell-type replaceable energy-dissipating beam segment is proposed. By weakening the web of the dumbbell-type energy-dissipating beam segment instead of the flange， the joint achieves higher lateral stiffness and a reduced risk of out-of-plane instability. At the same time， the dumbbell-type replaceable energy-dissipating beam segment is connected with high-strength bolts to improve replaceability. This design allows for the replacement of only the beam segment instead of the entire beam， thereby saving steel. Using the finite element analysis method， a parametric study was conducted to compare and analyze the effects of different parameters， including web weakening depth， web weakening length， and asymmetric weakening， on the seismic performance of the joint. A comparative analysis was performed on key structural responses， such as stress-strain contour plots， hysteresis curves， skeleton curves， energy dissipation curves， energy dissipation coefficients， and stiffness degradation curves under different structural parameters. The results showed that the web weakening length had the least influence on the structural behavior， followed by the web weakening depth， with asymmetric weakening having the most significant impact. The recommended value for the web weakening length is 0.24 to 0.48 times the length of the dumbbell-type beam segment， while the recommended value for the web weakening depth is 0.07 to 0.21 times its height.A symmetric weakening configuration is advised.
Aiming to address the problems of low lateral stiffness and difficult replacement in traditional flanged joints， a steel frame joint with a dumbbell-type replaceable energy-dissipating beam segment is proposed. By weakening the web of the dumbbell-type energy-dissipating beam segment instead of the flange， the joint achieves higher lateral stiffness and a reduced risk of out-of-plane instability. At the same time， the dumbbell-type replaceable energy-dissipating beam segment is connected with high-strength bolts to improve replaceability. This design allows for the replacement of only the beam segment instead of the entire beam， thereby saving steel. Using the finite element analysis method， a parametric study was conducted to compare and analyze the effects of different parameters， including web weakening depth， web weakening length， and asymmetric weakening， on the seismic performance of the joint. A comparative analysis was performed on key structural responses， such as stress-strain contour plots， hysteresis curves， skeleton curves， energy dissipation curves， energy dissipation coefficients， and stiffness degradation curves under different structural parameters. The results showed that the web weakening length had the least influence on the structural behavior， followed by the web weakening depth， with asymmetric weakening having the most significant impact. The recommended value for the web weakening length is 0.24 to 0.48 times the length of the dumbbell-type beam segment， while the recommended value for the web weakening depth is 0.07 to 0.21 times its height.A symmetric weakening configuration is advised.
2026, 56(4): 94-101.
doi: 10.3724/j.gyjzG25051903
Abstract:
This paper proposes a novel flat-corrugated steel plate shear wall （FCSPSW） and explores its elastic buckling performance along with the design and calculation methods for its stability bearing capacity. The FCSPSW is constructed by connecting flat and corrugated steel plate standard units. The latter are fabricated in a factory using a fully available and automatic production line， which ensures high production efficiency. Through the finite element numerical analysis of a large number of examples， the shear elastic buckling modes， elastic buckling loads， failure modes， instability mechanisms， and stability bearing capacity prediction for both welded and bolted connection types of FCSPSWs were studied respectively. This numerical investigation revealed the influence of different design parameters on the buckling and bearing capacity. Finally， design methods for predicting the shear stability bearing capacity of two types of FCSPSWs were proposed.
This paper proposes a novel flat-corrugated steel plate shear wall （FCSPSW） and explores its elastic buckling performance along with the design and calculation methods for its stability bearing capacity. The FCSPSW is constructed by connecting flat and corrugated steel plate standard units. The latter are fabricated in a factory using a fully available and automatic production line， which ensures high production efficiency. Through the finite element numerical analysis of a large number of examples， the shear elastic buckling modes， elastic buckling loads， failure modes， instability mechanisms， and stability bearing capacity prediction for both welded and bolted connection types of FCSPSWs were studied respectively. This numerical investigation revealed the influence of different design parameters on the buckling and bearing capacity. Finally， design methods for predicting the shear stability bearing capacity of two types of FCSPSWs were proposed.
2026, 56(4): 102-109.
doi: 10.3724/j.gyjzG23090501
Abstract:
Aiming at the construction safety of ultra-small-radius curved beam bracket system under complex soft soil foundation environment， taking the Dazonghu Interchange C-ramp bridge project of Fuli Expressway as the background， the finite element software MIDAS/Civil was used to establish the bracket system model， the stability problem of curved beam bracket system under complex soft soil foundation environment was studied. The influence of uneven settlement of the soft soil foundation， curvature radius of the curved beam， and bracket span， width， and height on the stability of the bracket system was analyzed. The results show that under the influence of uneven settlement of the soft soil foundation， the maximum stresses of the horizontal rods when bracket 1 and 2 lose stability are 82.32 MPa and 127.36 MPa， respectively， and none of the horizontal rods reaches the yield state. The instability of the bracket is caused by the insufficient stiffness of the pole itself. When the concrete of the beam body reaches a certain strength， the buckling load of the bracket increases with the increase of the curvature radius of the curved beam， and the buckling load of the bracket of the 120 m curvature radius increases by 93% compared with that of the 60 m curvature radius. The width and height of the bracket have a great influence on the stability of the bracket. Increasing the lateral width of the bracket and reducing the height of the bracket will improve the stability of the bracket. Compared with the bracket width of 16.5 m， the buckling load of the bracket width of 22.5 m increases by 62.34%. Based on the research results， the sedimentation monitoring was conducted on the bracket system， and on-site monitoring showed that the bracket sedimentation monitoring data were within the specified range， indicating that the bracket method has good feasibility and safety for construction under soft foundation conditions.
Aiming at the construction safety of ultra-small-radius curved beam bracket system under complex soft soil foundation environment， taking the Dazonghu Interchange C-ramp bridge project of Fuli Expressway as the background， the finite element software MIDAS/Civil was used to establish the bracket system model， the stability problem of curved beam bracket system under complex soft soil foundation environment was studied. The influence of uneven settlement of the soft soil foundation， curvature radius of the curved beam， and bracket span， width， and height on the stability of the bracket system was analyzed. The results show that under the influence of uneven settlement of the soft soil foundation， the maximum stresses of the horizontal rods when bracket 1 and 2 lose stability are 82.32 MPa and 127.36 MPa， respectively， and none of the horizontal rods reaches the yield state. The instability of the bracket is caused by the insufficient stiffness of the pole itself. When the concrete of the beam body reaches a certain strength， the buckling load of the bracket increases with the increase of the curvature radius of the curved beam， and the buckling load of the bracket of the 120 m curvature radius increases by 93% compared with that of the 60 m curvature radius. The width and height of the bracket have a great influence on the stability of the bracket. Increasing the lateral width of the bracket and reducing the height of the bracket will improve the stability of the bracket. Compared with the bracket width of 16.5 m， the buckling load of the bracket width of 22.5 m increases by 62.34%. Based on the research results， the sedimentation monitoring was conducted on the bracket system， and on-site monitoring showed that the bracket sedimentation monitoring data were within the specified range， indicating that the bracket method has good feasibility and safety for construction under soft foundation conditions.
2026, 56(4): 110-121.
doi: 10.3724/j.gyjzG24093003
Abstract:
Efficient and safe temporary installation and fixing of prefabricated components has become a key issue in construction， with the continuous growth rate of the development of construction industrialization. This paper analyses the shortcomings of the existing support system in the installation of multi-category prefabricated components， pointing out its limitations in terms of adaptability to working conditions， convenience of adjustment， and reliability of support. Subsequently， through the introduction of adjustable support technology and modular design concepts， the fixed support system is optimized based on the form characteristics of precast components， to meet the needs of different precast component sizes， weights and installation locations， and to provide higher support stability. The application of actual engineering cases shows that the optimized support system shows significant advantages in improving installation efficiency， reducing the consumption of support materials and enhancing construction safety. It can not only effectively reduce the construction period， but also reduce the construction cost， and further enhance the flexibility and safety of on-site construction. This provides a new idea for the development of complex working conditions installation， and modular rapid construction of prefabricated components.
Efficient and safe temporary installation and fixing of prefabricated components has become a key issue in construction， with the continuous growth rate of the development of construction industrialization. This paper analyses the shortcomings of the existing support system in the installation of multi-category prefabricated components， pointing out its limitations in terms of adaptability to working conditions， convenience of adjustment， and reliability of support. Subsequently， through the introduction of adjustable support technology and modular design concepts， the fixed support system is optimized based on the form characteristics of precast components， to meet the needs of different precast component sizes， weights and installation locations， and to provide higher support stability. The application of actual engineering cases shows that the optimized support system shows significant advantages in improving installation efficiency， reducing the consumption of support materials and enhancing construction safety. It can not only effectively reduce the construction period， but also reduce the construction cost， and further enhance the flexibility and safety of on-site construction. This provides a new idea for the development of complex working conditions installation， and modular rapid construction of prefabricated components.
2026, 56(4): 122-129.
doi: 10.3724/j.gyjzG24120303
Abstract:
In order to investigate the distribution and development of temperature-induced shrinkage stress in concrete raft foundations constructed using the alternative-bay construction method， large-scale model experiments and analysis were conducted in this paper. Firstly， a reinforced concrete raft test model was designed employing both the alternative-bay construction method and post-pour strip construction method. The temperature and stress-strain variations of the structure were measured and analyzed， and the stress distribution patterns of different construction methods were compared and analyzed. Secondly， a numerical model based on the finite element software MIDAS FEA was established and verified against the experimental results. The research results indicated that under the two construction methods， the temperature and stress development trends of the concrete bottom slab section were similar， as were the magnitude and distribution of stress along the slab length. However， due to changes in constraint conditions， the stress variation pattern in the post-pour bottom slab of the alternative-bay construction method differed from that in the other slabs， with the stress in the middle section being greater than that in the post-pour strip method. Therefore， when using the alternative-bay construction method， it is necessary to control the stress in the middle section to ensure it does not exceed the tensile strength， thereby preventing cracking in the bottom slab.
In order to investigate the distribution and development of temperature-induced shrinkage stress in concrete raft foundations constructed using the alternative-bay construction method， large-scale model experiments and analysis were conducted in this paper. Firstly， a reinforced concrete raft test model was designed employing both the alternative-bay construction method and post-pour strip construction method. The temperature and stress-strain variations of the structure were measured and analyzed， and the stress distribution patterns of different construction methods were compared and analyzed. Secondly， a numerical model based on the finite element software MIDAS FEA was established and verified against the experimental results. The research results indicated that under the two construction methods， the temperature and stress development trends of the concrete bottom slab section were similar， as were the magnitude and distribution of stress along the slab length. However， due to changes in constraint conditions， the stress variation pattern in the post-pour bottom slab of the alternative-bay construction method differed from that in the other slabs， with the stress in the middle section being greater than that in the post-pour strip method. Therefore， when using the alternative-bay construction method， it is necessary to control the stress in the middle section to ensure it does not exceed the tensile strength， thereby preventing cracking in the bottom slab.
2026, 56(4): 130-140.
doi: 10.3724/j.gyjzG24042901
Abstract:
To investigate the dynamic response of reinforced concrete frame structures under indoor explosion conditions， the study explored the failure modes of reinforced concrete slabs and beam-column joints through numerical simulation methods. Based on existing experimental data of reinforced concrete frame structures under internal explosion loads， a segregated single-layer single-span reduced-scale three-dimensional finite element model was established using the finite element software ANSYS/LS-DYNA. This study considered the shock wave propagation of explosive charge in the air domain， the fluid-structure coupling effect， and the influence of strain rate parameters on the material constitutive model. The simulation modeled the explosion of a 200 g explosive charge in the central area of the frame. The simulated results were in good agreement with the experimental results， validating the correctness of the material and parameter settings in the model. Additionally， the failure processes of the slabs and beams were analyzed， and overall， failure predominantly occurred at the junctions of the slab-beam and beam-column. By applying a controlled variable method， this study investigated the influence of parameters such as concrete strength grade and slab and beam reinforcement methods on the blast resistance of reinforced concrete frame structures. The results indicated that increasing the concrete strength grade enhanced the structure's blast resistance. However， after a certain degree of increase in concrete strength grade， further increments did not yield significant improvements. Using double-layer bidirectional reinforcement slightly reduced vertical displacement and concrete cracking in the top slab. Increasing the rebar diameter significantly reduced slab displacement but might increase concrete cracking. Properly shortening the length of rebars extending from the slab into the beam enhanced the blast resistance of the slab. To improve the blast resistance of frame beams， the method of increasing the diameter of longitudinal reinforcement inside the beam should be considered first， followed by the application of enhanced hoop reinforcement in heavily damaged areas. Increasing the diameter of the internal reinforcement of the reinforced concrete frame can improve overall blast resistance.
To investigate the dynamic response of reinforced concrete frame structures under indoor explosion conditions， the study explored the failure modes of reinforced concrete slabs and beam-column joints through numerical simulation methods. Based on existing experimental data of reinforced concrete frame structures under internal explosion loads， a segregated single-layer single-span reduced-scale three-dimensional finite element model was established using the finite element software ANSYS/LS-DYNA. This study considered the shock wave propagation of explosive charge in the air domain， the fluid-structure coupling effect， and the influence of strain rate parameters on the material constitutive model. The simulation modeled the explosion of a 200 g explosive charge in the central area of the frame. The simulated results were in good agreement with the experimental results， validating the correctness of the material and parameter settings in the model. Additionally， the failure processes of the slabs and beams were analyzed， and overall， failure predominantly occurred at the junctions of the slab-beam and beam-column. By applying a controlled variable method， this study investigated the influence of parameters such as concrete strength grade and slab and beam reinforcement methods on the blast resistance of reinforced concrete frame structures. The results indicated that increasing the concrete strength grade enhanced the structure's blast resistance. However， after a certain degree of increase in concrete strength grade， further increments did not yield significant improvements. Using double-layer bidirectional reinforcement slightly reduced vertical displacement and concrete cracking in the top slab. Increasing the rebar diameter significantly reduced slab displacement but might increase concrete cracking. Properly shortening the length of rebars extending from the slab into the beam enhanced the blast resistance of the slab. To improve the blast resistance of frame beams， the method of increasing the diameter of longitudinal reinforcement inside the beam should be considered first， followed by the application of enhanced hoop reinforcement in heavily damaged areas. Increasing the diameter of the internal reinforcement of the reinforced concrete frame can improve overall blast resistance.
2026, 56(4): 141-150.
doi: 10.3724/j.gyjzG23080712
Abstract:
In the double-steel-plate composite shear wall of the cistern in a nuclear power plant reactor， stainless steel plates are usually installed on the surface of low-alloy steel to prevent steel plate corrosion. In order to implement the modular design for structural anti-corrosion， a stainless steel-concrete-normal steel sandwich composite shear wall was proposed， and quasi-static loading tests were conducted on three 1∶5 scale specimens in the plane. The failure modes， hysteretic curves， skeleton curves， stiffness degradation， ductility， and energy consumption of the shear wall were obtained. The effects of steel plate material， equal-thickness design， and equal-strength design on the seismic performance of shear wall were analyzed. The results showed that the stainless steel-concrete-normal steel sandwich composite shear wall exhibited good seismic performance， and its bearing capacity and lateral stiffness could be effectively improved with the increase of steel plate strength and steel ratio. The final failure mode of each specimen was bending failure. Based on the test results， the calculation model of the shear wall was established， and the simplified calculation formula for the compressive bending capacity was proposed. The feasibility of the formula was verified by comparison with experimental results.
In the double-steel-plate composite shear wall of the cistern in a nuclear power plant reactor， stainless steel plates are usually installed on the surface of low-alloy steel to prevent steel plate corrosion. In order to implement the modular design for structural anti-corrosion， a stainless steel-concrete-normal steel sandwich composite shear wall was proposed， and quasi-static loading tests were conducted on three 1∶5 scale specimens in the plane. The failure modes， hysteretic curves， skeleton curves， stiffness degradation， ductility， and energy consumption of the shear wall were obtained. The effects of steel plate material， equal-thickness design， and equal-strength design on the seismic performance of shear wall were analyzed. The results showed that the stainless steel-concrete-normal steel sandwich composite shear wall exhibited good seismic performance， and its bearing capacity and lateral stiffness could be effectively improved with the increase of steel plate strength and steel ratio. The final failure mode of each specimen was bending failure. Based on the test results， the calculation model of the shear wall was established， and the simplified calculation formula for the compressive bending capacity was proposed. The feasibility of the formula was verified by comparison with experimental results.
2026, 56(4): 151-158.
doi: 10.3724/j.gyjzG23090909
Abstract:
Aiming at the thermo-mechanical coupling effects in energy piles during operation， the controlling differential equations for the pile displacement function and the soil vertical displacement transfer function were established based on energy principles and the variational method. The unknown constants were determined using boundary conditions. The analytical solutions for the thermomechanical behavior of end-bearing energy piles and friction energy piles under arbitrary thermo-mechanical load combinations were derived. Compared with the experimental results， the accuracy and rationality of the proposed method were verified， and the influence of slenderness ratio and temperature variations on the mechanical behavior of end-bearing energy piles and floating energy piles was further investigated.
Aiming at the thermo-mechanical coupling effects in energy piles during operation， the controlling differential equations for the pile displacement function and the soil vertical displacement transfer function were established based on energy principles and the variational method. The unknown constants were determined using boundary conditions. The analytical solutions for the thermomechanical behavior of end-bearing energy piles and friction energy piles under arbitrary thermo-mechanical load combinations were derived. Compared with the experimental results， the accuracy and rationality of the proposed method were verified， and the influence of slenderness ratio and temperature variations on the mechanical behavior of end-bearing energy piles and floating energy piles was further investigated.
2026, 56(4): 159-165.
doi: 10.3724/j.gyjzG24011008
Abstract:
The p-y curve for laterally loaded piles in saturated sand is related to the internal friction angle φ. However， the coefficient m used in the m-method is selected from empirical ranges in code tables and is not linked to φ. Under the condition of the same allowable pile-head displacement， the horizontal load H0 calculated by p-y curve method can be substituted into the m-method model to determine the corresponding m value. Based on extensive numerical calculations， relations were established among the internal friction angle φ， pile diameter， allowable pile-head displacement， and the coefficient m for saturated sand. These results were presented as formulas and tables to allow for convenient lookup. It was found that the stiffness of the pile shaft had a negligible influence on these relations. In three practical cases， the allowable lateral bearing capacities computed with the m values from this method showed good agreement with the measured results.
The p-y curve for laterally loaded piles in saturated sand is related to the internal friction angle φ. However， the coefficient m used in the m-method is selected from empirical ranges in code tables and is not linked to φ. Under the condition of the same allowable pile-head displacement， the horizontal load H0 calculated by p-y curve method can be substituted into the m-method model to determine the corresponding m value. Based on extensive numerical calculations， relations were established among the internal friction angle φ， pile diameter， allowable pile-head displacement， and the coefficient m for saturated sand. These results were presented as formulas and tables to allow for convenient lookup. It was found that the stiffness of the pile shaft had a negligible influence on these relations. In three practical cases， the allowable lateral bearing capacities computed with the m values from this method showed good agreement with the measured results.
2026, 56(4): 166-177.
doi: 10.3724/j.gyjzG24090602
Abstract:
As a type of anti-floating anchor， under-reamed ground anti-floating anchors with capsule features factory-manufactured key components and on-site rapidly assembly technology， enabling efficient construction and reliable quality control. They have been widely used in anti-floating anchoring engineering and are favored by many engineers and technicians because of their remarkable features， such as large anchoring force， small deformation， and multiple anti-corrosion functions. In order to standardize their design， construction， and quality inspection， the Technical Specification for Under-reamed Ground Anchors with Capsule（T/CECS 1259-2023） was promulgated and implemented on June 1， 2023. Addressing key concerns in engineering design， such as determining the ultimate pullout capacity and load-displacement characteristics of under-reamed ground anti-floating anchors with capsule， this paper analyzed the field test results. Based on existing methods for calculating the characteristic ultimate pullout capacity of the anchor plates in sand and clay， this study proposed respective prediction methods and calculation formulas for the ultimate pullout capacity of under-reamed ground anti-floating anchors with capsule. The feasibility of their application without prestress was discussed， offering design guidance for using them as structural tension members in anti-floating engineering.
As a type of anti-floating anchor， under-reamed ground anti-floating anchors with capsule features factory-manufactured key components and on-site rapidly assembly technology， enabling efficient construction and reliable quality control. They have been widely used in anti-floating anchoring engineering and are favored by many engineers and technicians because of their remarkable features， such as large anchoring force， small deformation， and multiple anti-corrosion functions. In order to standardize their design， construction， and quality inspection， the Technical Specification for Under-reamed Ground Anchors with Capsule（T/CECS 1259-2023） was promulgated and implemented on June 1， 2023. Addressing key concerns in engineering design， such as determining the ultimate pullout capacity and load-displacement characteristics of under-reamed ground anti-floating anchors with capsule， this paper analyzed the field test results. Based on existing methods for calculating the characteristic ultimate pullout capacity of the anchor plates in sand and clay， this study proposed respective prediction methods and calculation formulas for the ultimate pullout capacity of under-reamed ground anti-floating anchors with capsule. The feasibility of their application without prestress was discussed， offering design guidance for using them as structural tension members in anti-floating engineering.
2026, 56(4): 178-186.
doi: 10.3724/j.gyjzG24083102
Abstract:
The purpose of this study is to investigate the difference of static mechanical characteristics of combined helical pile （CHP） composite foundation under uplift-horizontal combined loading and unidirectional horizontal loading. The coupled Euler-Lagrange （CEL） method was used for finite element （FE） analysis. The accuracy and rationality of the FE model were verified by comparing the FE analysis results with the test results. This validated model was used to analyze the static mechanical characteristics， such as ultimate bearing capacities， initial stiffnesses， stress distributions and failure modes of the CHP composite foundation under the combined uplift-horizontal loading. When the uplift displacement was 0.2， 0.4， 0.6， 0.8， and 1.0 times the uplift control displacement， the horizontal ultimate bearing capacity decreased by 6.5 %， 11.3 %， 13.4 %， 17.3 %， and 22%， respectively， and the initial stiffness varied by no more than 4.5 %， showing that the method for controlling the ultimate bearing capacity using the limit lateral shift （e.g.， 40 mm） had a large enough safety margin. The plastic strain of the soil first appeared at the edge of the bottom anchor， then at the edge of the middle anchor plate， and finally gradually expanded upward through the upper and lower regions.
The purpose of this study is to investigate the difference of static mechanical characteristics of combined helical pile （CHP） composite foundation under uplift-horizontal combined loading and unidirectional horizontal loading. The coupled Euler-Lagrange （CEL） method was used for finite element （FE） analysis. The accuracy and rationality of the FE model were verified by comparing the FE analysis results with the test results. This validated model was used to analyze the static mechanical characteristics， such as ultimate bearing capacities， initial stiffnesses， stress distributions and failure modes of the CHP composite foundation under the combined uplift-horizontal loading. When the uplift displacement was 0.2， 0.4， 0.6， 0.8， and 1.0 times the uplift control displacement， the horizontal ultimate bearing capacity decreased by 6.5 %， 11.3 %， 13.4 %， 17.3 %， and 22%， respectively， and the initial stiffness varied by no more than 4.5 %， showing that the method for controlling the ultimate bearing capacity using the limit lateral shift （e.g.， 40 mm） had a large enough safety margin. The plastic strain of the soil first appeared at the edge of the bottom anchor， then at the edge of the middle anchor plate， and finally gradually expanded upward through the upper and lower regions.
2026, 56(4): 187-198.
doi: 10.3724/j.gyjzG24050801
Abstract:
In recent years， with the gradual expansion and development of high-voltage transmission lines and offshore wind power， spiral anchors have been applied in fields such as construction and power engineering. Therefore， higher demands have been put forward for the basic load-bearing performance and usage scenarios. However， the current calculation model for the basic bearing capacity of helical anchors is only proposed for sand and clay. When the soil exhibits cohesive force and internal friction angle simultaneously in the soil conditions， the applicability of the bearing capacity calculation formula has not been fully validated. Therefore， this study conducted in-situ experimental research and numerical analysis on inclined helical single anchors in silty clay， elucidated the force transmission path under the tension and compression loads of inclined helical anchors， revealed the failure modes in complex stratified soils， demonstrated the applicability of the current bearing capacity calculation methods for silty clay， and established a vertical deformation calculation model for helical anchors based on the t-z curve method. The results indicated that the soil disturbance caused by helical anchor drilling resulted in a higher compressive bearing capacity than an uplift bearing capacity. The load borne by the top anchor plate under upward and compression conditions accounted for about 15% of the total load. When calculating the bearing capacity according to the regulation， it was not appropriate to consider both c and φ simultaneously； instead， they should be considered separately. When the corrected bearing capacity matched the actual bearing capacity well， the calculated vertical deformation and load displacement curves matched well， and the theoretical formula demonstrated high prediction accuracy.
In recent years， with the gradual expansion and development of high-voltage transmission lines and offshore wind power， spiral anchors have been applied in fields such as construction and power engineering. Therefore， higher demands have been put forward for the basic load-bearing performance and usage scenarios. However， the current calculation model for the basic bearing capacity of helical anchors is only proposed for sand and clay. When the soil exhibits cohesive force and internal friction angle simultaneously in the soil conditions， the applicability of the bearing capacity calculation formula has not been fully validated. Therefore， this study conducted in-situ experimental research and numerical analysis on inclined helical single anchors in silty clay， elucidated the force transmission path under the tension and compression loads of inclined helical anchors， revealed the failure modes in complex stratified soils， demonstrated the applicability of the current bearing capacity calculation methods for silty clay， and established a vertical deformation calculation model for helical anchors based on the t-z curve method. The results indicated that the soil disturbance caused by helical anchor drilling resulted in a higher compressive bearing capacity than an uplift bearing capacity. The load borne by the top anchor plate under upward and compression conditions accounted for about 15% of the total load. When calculating the bearing capacity according to the regulation， it was not appropriate to consider both c and φ simultaneously； instead， they should be considered separately. When the corrected bearing capacity matched the actual bearing capacity well， the calculated vertical deformation and load displacement curves matched well， and the theoretical formula demonstrated high prediction accuracy.
2026, 56(4): 199-207.
doi: 10.3724/j.gyjzG24042810
Abstract:
Based on a shield tunnel project of Nanjing Metro， a method was developed to reuse composite shield muck by utilizing fine sand and silty clay as replacement materials for conventional backfill grouting materials. The influence of factors such as the water-to-binder（cement + fly ash） ratio， cement-to-fly ash ratio， and binder-to-clay ratio on the performance of composite muck slurry was revealed， ultimately obtaining an optimal slurry mix proportion. The results showed that the composite muck could replace raw materials for backfill grouting to produce a muck slurry that met field requirements. The optimal mix proportion obtained was as follows： a water-to-binder ratio of 0.7， cement-to-fly ash ratio of 0.6， binder-to-clay ratio of 0.6， clay-to-sand ratio of 0.2， with a substitution ratio of 0.75. Under this mix proportion， the slurry demonstrated significant advantages in strength and bleeding rate while maintaining good fluidity， which could reduce costs by up to 37.8%.
Based on a shield tunnel project of Nanjing Metro， a method was developed to reuse composite shield muck by utilizing fine sand and silty clay as replacement materials for conventional backfill grouting materials. The influence of factors such as the water-to-binder（cement + fly ash） ratio， cement-to-fly ash ratio， and binder-to-clay ratio on the performance of composite muck slurry was revealed， ultimately obtaining an optimal slurry mix proportion. The results showed that the composite muck could replace raw materials for backfill grouting to produce a muck slurry that met field requirements. The optimal mix proportion obtained was as follows： a water-to-binder ratio of 0.7， cement-to-fly ash ratio of 0.6， binder-to-clay ratio of 0.6， clay-to-sand ratio of 0.2， with a substitution ratio of 0.75. Under this mix proportion， the slurry demonstrated significant advantages in strength and bleeding rate while maintaining good fluidity， which could reduce costs by up to 37.8%.
2026, 56(4): 208-216.
doi: 10.3724/j.gyjzG24082301
Abstract:
The influence of natural environmental effects on the strength of silt improved by nano-silica and lime was studied through a series of tests of dry-wet， freeze-thaw， and dry-wet and freeze-thaw coupling. Through electron microscopy scanning experiments， the microstructure of improved silt under the action of natural environment was analyzed. The results showed that the axial stress-strain relationship of the improved silt exhibited obvious brittle failure characteristics under the action of different cyclic modes， such as dry-wet， freeze-thaw， and dry-wet and freeze-thaw coupling， etc. ， the axial strain （failure strain） corresponding to the peak stress was between 1.0% and 1.5%. Except for the first cycle， the strength of the improved silt decreased with the increase of the number of cycles and tended to be stable gradually under the action of different cycles. The reducing effect of freeze-thaw cycles on the strength of improved silt was greater than that of dry-wet cycles， and the reducing effect of freeze-thaw cycles on the strength of improved silt was strengthened when the two cycles were coupled. Dry-wet and freeze-thaw cycles reduced the cohesion of improved silt， but the decrease of internal friction angle was mainly affected by dry-wet cycles. The dry-wet and freeze-thaw cycles damaged the soil structure， leading to an increase in the proportion of medium and large pores in the soil， which is the main reason for the deterioration of soil strength. The improved silt met the strength requirements of the railway embankment fillers under different cycling modes， and the improved silt with nano-silica and lime had a strong capacity to resist the influence of environmental factors.
The influence of natural environmental effects on the strength of silt improved by nano-silica and lime was studied through a series of tests of dry-wet， freeze-thaw， and dry-wet and freeze-thaw coupling. Through electron microscopy scanning experiments， the microstructure of improved silt under the action of natural environment was analyzed. The results showed that the axial stress-strain relationship of the improved silt exhibited obvious brittle failure characteristics under the action of different cyclic modes， such as dry-wet， freeze-thaw， and dry-wet and freeze-thaw coupling， etc. ， the axial strain （failure strain） corresponding to the peak stress was between 1.0% and 1.5%. Except for the first cycle， the strength of the improved silt decreased with the increase of the number of cycles and tended to be stable gradually under the action of different cycles. The reducing effect of freeze-thaw cycles on the strength of improved silt was greater than that of dry-wet cycles， and the reducing effect of freeze-thaw cycles on the strength of improved silt was strengthened when the two cycles were coupled. Dry-wet and freeze-thaw cycles reduced the cohesion of improved silt， but the decrease of internal friction angle was mainly affected by dry-wet cycles. The dry-wet and freeze-thaw cycles damaged the soil structure， leading to an increase in the proportion of medium and large pores in the soil， which is the main reason for the deterioration of soil strength. The improved silt met the strength requirements of the railway embankment fillers under different cycling modes， and the improved silt with nano-silica and lime had a strong capacity to resist the influence of environmental factors.
2026, 56(4): 217-224.
doi: 10.3724/j.gyjzG23070416
Abstract:
Among the two major states of chromium， Cr（VI） is high mobile and carcinogenic whereas Cr（III） is less toxic. Remediation of chromium-contaminated soil usually involves reducing Cr（VI） to Cr（III） and subsequently immobilizing it. In this paper， a combined remediation technique including reduction， adsorption， and solidification was proposed. By employing an adsorbent， the remediation effectiveness was improved and the amount of reducing and curing agent was to some extent decreased. Synthetic precipitation leaching procedure （SPLP）， unconfined compressive strength （UCS）， and acid neutralization capacity （ANC） tests were carried out to evaluate the remediation effect of different agent combinations and different addition procedures. SPLP tests showed that the reduction-adsorption-solidification treatment significantly reduced the leached chromium. Using calcium polysulfide as the reducing agent was more effective than using ferrous sulfate. UCS tests showed that the strength of the solidified soil was reduced after employing the adsorbent， but the standards for strength could still be satisfied. ANC tests demonstrated that the combined remediation technology improved the capacity of the solidified system to resist acid erosion. The best combined dosage was calcium polysulfide， vermiculite， and cement. The researches on adding procedures showed that adding the reducing agent and adsorbent together and then adding the curing agent achieved similar effects to adding the three agents separately. This could facilitate the remediation process.
Among the two major states of chromium， Cr（VI） is high mobile and carcinogenic whereas Cr（III） is less toxic. Remediation of chromium-contaminated soil usually involves reducing Cr（VI） to Cr（III） and subsequently immobilizing it. In this paper， a combined remediation technique including reduction， adsorption， and solidification was proposed. By employing an adsorbent， the remediation effectiveness was improved and the amount of reducing and curing agent was to some extent decreased. Synthetic precipitation leaching procedure （SPLP）， unconfined compressive strength （UCS）， and acid neutralization capacity （ANC） tests were carried out to evaluate the remediation effect of different agent combinations and different addition procedures. SPLP tests showed that the reduction-adsorption-solidification treatment significantly reduced the leached chromium. Using calcium polysulfide as the reducing agent was more effective than using ferrous sulfate. UCS tests showed that the strength of the solidified soil was reduced after employing the adsorbent， but the standards for strength could still be satisfied. ANC tests demonstrated that the combined remediation technology improved the capacity of the solidified system to resist acid erosion. The best combined dosage was calcium polysulfide， vermiculite， and cement. The researches on adding procedures showed that adding the reducing agent and adsorbent together and then adding the curing agent achieved similar effects to adding the three agents separately. This could facilitate the remediation process.
2026, 56(4): 225-232.
doi: 10.3724/j.gyjzG23082104
Abstract:
Monopile is a widely-used foundation form for offshore wind power. The seabed conditions in the sea area of Guangdong，harsh environment loads，and continuous development into deeper seas have lead to the wider application of large-diameter monopiles in offshore wind farms in shallow water area. At present，the monopile foundation design in China mainly adopts the p-y curve method. This method is based on the test of small-diameter long flexible piles，which underestimates the stiffness and bearing capacity of large-diameter monopile pile-soil interaction and increases construction costs and construction difficulties. By comparing the mainstream monopile foundation design methods in Europe，an improved pile-soil interaction analysis and optimized design method for large-diameter monopile foundations in offshore wind power has been established. The key technology is based on the multi-spring model proposed by NGI，combined with the results of in-situ CPTU tests and geotechnical tests，which can more accurately simulate the pile-soil interaction effect and achieve refined design of large-diameter monopile foundations for offshore wind power.
Monopile is a widely-used foundation form for offshore wind power. The seabed conditions in the sea area of Guangdong，harsh environment loads，and continuous development into deeper seas have lead to the wider application of large-diameter monopiles in offshore wind farms in shallow water area. At present，the monopile foundation design in China mainly adopts the p-y curve method. This method is based on the test of small-diameter long flexible piles，which underestimates the stiffness and bearing capacity of large-diameter monopile pile-soil interaction and increases construction costs and construction difficulties. By comparing the mainstream monopile foundation design methods in Europe，an improved pile-soil interaction analysis and optimized design method for large-diameter monopile foundations in offshore wind power has been established. The key technology is based on the multi-spring model proposed by NGI，combined with the results of in-situ CPTU tests and geotechnical tests，which can more accurately simulate the pile-soil interaction effect and achieve refined design of large-diameter monopile foundations for offshore wind power.
2026, 56(4): 233-240.
doi: 10.3724/j.gyjzG24102901
Abstract:
In view of the current situation where a large quantity of waste soil from highway engineering is difficult to absorb on a large scale， this paper proposed a new type of modified waste soil precast pile based on a weak subgrade reinforcement project. It also conducted related research on the machinery for forming modified waste soil precast piles， the pile forming process， and the construction technology for reinforcing weak subgrads using these piles. The physical and mechanical properties of the waste soil in the field were obtained by laboratory tests， and the optimal cement content of the waste cohesive soil was determined. Based on the static load test results， the application effectiveness of modified waste soil precast piles in reinforcing weak subgrads was studied， and the load transfer characteristics of these piles were analyzed. By normalizing the field-measured data， a softening model of pile side friction resistance considering the interface bonding characteristics was proposed. The relevant research results provide new insights for the resource utilization of waste soil and reinforcement of weak subgrads.
In view of the current situation where a large quantity of waste soil from highway engineering is difficult to absorb on a large scale， this paper proposed a new type of modified waste soil precast pile based on a weak subgrade reinforcement project. It also conducted related research on the machinery for forming modified waste soil precast piles， the pile forming process， and the construction technology for reinforcing weak subgrads using these piles. The physical and mechanical properties of the waste soil in the field were obtained by laboratory tests， and the optimal cement content of the waste cohesive soil was determined. Based on the static load test results， the application effectiveness of modified waste soil precast piles in reinforcing weak subgrads was studied， and the load transfer characteristics of these piles were analyzed. By normalizing the field-measured data， a softening model of pile side friction resistance considering the interface bonding characteristics was proposed. The relevant research results provide new insights for the resource utilization of waste soil and reinforcement of weak subgrads.
2026, 56(4): 241-248.
doi: 10.3724/j.gyjzG23071312
Abstract:
This study analyzed the soil displacement effect during high-pressure rotary jet pile construction by simplifying the construction process as a series of pressure-controlled spherical cavity expansions in a semi-infinite soil medium. Based on the elastic-plastic solution of pressure-controlled spherical cavity expansion theory， a calculation method was proposed to estimate the soil displacement caused by high-pressure rotary jet pile construction. Nonlinear contact theory between the pile and soil was introduced， and the finite difference method was employed to determine the internal forces and deformations of the pile. The proposed method was applied to field construction cases， and its validity was verified by comparing the results with on-site monitoring data. Additionally， a parametric study was conducted. The research findings revealed that the soil displacement effect decreased with depth and primarily occurred in shallow soil layers during the construction of individual high-pressure rotary jet piles. The lateral displacement at the ground surface increased first and then decreased with the increase in horizontal distance， while the ground uplift exhibited an exponential decay trend. The maximum lateral displacement of existing piles was observed at the pile head， and the maximum bending moment occurred in the middle section of the pile. The construction time interval had the greatest influence on the response of adjacent piles. Therefore， to mitigate soil displacement effects， it is recommended to adopt construction techniques such as skip-hole drilling and spaced pile installation.
This study analyzed the soil displacement effect during high-pressure rotary jet pile construction by simplifying the construction process as a series of pressure-controlled spherical cavity expansions in a semi-infinite soil medium. Based on the elastic-plastic solution of pressure-controlled spherical cavity expansion theory， a calculation method was proposed to estimate the soil displacement caused by high-pressure rotary jet pile construction. Nonlinear contact theory between the pile and soil was introduced， and the finite difference method was employed to determine the internal forces and deformations of the pile. The proposed method was applied to field construction cases， and its validity was verified by comparing the results with on-site monitoring data. Additionally， a parametric study was conducted. The research findings revealed that the soil displacement effect decreased with depth and primarily occurred in shallow soil layers during the construction of individual high-pressure rotary jet piles. The lateral displacement at the ground surface increased first and then decreased with the increase in horizontal distance， while the ground uplift exhibited an exponential decay trend. The maximum lateral displacement of existing piles was observed at the pile head， and the maximum bending moment occurred in the middle section of the pile. The construction time interval had the greatest influence on the response of adjacent piles. Therefore， to mitigate soil displacement effects， it is recommended to adopt construction techniques such as skip-hole drilling and spaced pile installation.
2026, 56(4): 249-255.
doi: 10.3724/j.gyjzG23092007
Abstract:
To explore the timeliness of boundary drainage and the consolidation characteristics of double-layered soil under non-Darcy flow conditions， the one-dimensional consolidation problem of double-layered foundation based on the exponential flow model was studied by introducing continuous drainage boundary conditions. Firstly， the finite difference method was used to solve the two-layered foundation consolidation with exponential flow under continuous drainage boundaries and obtain corresponding solutions， which were then compared and validated against existing research. Then， based on the deduction results， the effects of interface parameters， thickness ratio of upper to lower soil layers， permeability ratio of soil layers， and ratio of compression coefficients on the consolidation degree of the foundation were analyzed. The research results indicated that the larger the interface parameters， the faster the consolidation. However， as the flow index increased， the influence of the interface parameters on the consolidation rate of the double-layered foundation decreased. For the foundation with an upper soft and lower hard layer， a thicker lower harder layer led to faster consolidation； in contrast， for the upper hard and lower soft type， a thicker upper hard layer resulted in a slower consolidation rate. Compared with the flow index of the lower soil， the flow index of the upper soil had a greater impact on the consolidation of the foundation. Therefore， in order to accelerate the consolidation speed of the soil， different soil layers with different properties should be reasonably arranged during construction.
To explore the timeliness of boundary drainage and the consolidation characteristics of double-layered soil under non-Darcy flow conditions， the one-dimensional consolidation problem of double-layered foundation based on the exponential flow model was studied by introducing continuous drainage boundary conditions. Firstly， the finite difference method was used to solve the two-layered foundation consolidation with exponential flow under continuous drainage boundaries and obtain corresponding solutions， which were then compared and validated against existing research. Then， based on the deduction results， the effects of interface parameters， thickness ratio of upper to lower soil layers， permeability ratio of soil layers， and ratio of compression coefficients on the consolidation degree of the foundation were analyzed. The research results indicated that the larger the interface parameters， the faster the consolidation. However， as the flow index increased， the influence of the interface parameters on the consolidation rate of the double-layered foundation decreased. For the foundation with an upper soft and lower hard layer， a thicker lower harder layer led to faster consolidation； in contrast， for the upper hard and lower soft type， a thicker upper hard layer resulted in a slower consolidation rate. Compared with the flow index of the lower soil， the flow index of the upper soil had a greater impact on the consolidation of the foundation. Therefore， in order to accelerate the consolidation speed of the soil， different soil layers with different properties should be reasonably arranged during construction.
2026, 56(4): 256-265.
doi: 10.3724/j.gyjzG23122701
Abstract:
In order to study the seismic performance of a large-section rectangular prefabricated metro station structure constructed by pipe jacking， quasi-static tests were conducted on a 1∶5 scale model of the overall structure and a full-scale model of the longitudinal joint. The test results indicated that during the quasi-static test of the scaled model， the horizontal force at the initial appearance of cracks was approximately 7.5 times the design seismic action. When the top horizontal force at the top of the structure reached 9 times the design seismic action， the skeleton curve of the structure remained essentially in the elastic stage. The hysteresis curve of the joint generally presented a spindle shape， with a discernible descending section after reaching the peak load. Moreover， the joint maintained strong energy dissipation capacity after reaching the peak load， indicating satisfactory seismic performance. The lining structure and joint form adopted in the metro station are reasonable， and its seismic performance meets the design requirements.
In order to study the seismic performance of a large-section rectangular prefabricated metro station structure constructed by pipe jacking， quasi-static tests were conducted on a 1∶5 scale model of the overall structure and a full-scale model of the longitudinal joint. The test results indicated that during the quasi-static test of the scaled model， the horizontal force at the initial appearance of cracks was approximately 7.5 times the design seismic action. When the top horizontal force at the top of the structure reached 9 times the design seismic action， the skeleton curve of the structure remained essentially in the elastic stage. The hysteresis curve of the joint generally presented a spindle shape， with a discernible descending section after reaching the peak load. Moreover， the joint maintained strong energy dissipation capacity after reaching the peak load， indicating satisfactory seismic performance. The lining structure and joint form adopted in the metro station are reasonable， and its seismic performance meets the design requirements.
2026, 56(4): 266-273.
doi: 10.3724/j.gyjzG24103112
Abstract:
In order to explore the optimization method of solidification performance using microbially induced calcium carbonate precipitation （MICP） technology， a study was conducted based on MICP combined with additive technology， using calcium acetate as the calcium source. The effect and micro-mechanism of aluminum chloride additive on the optimization of MICP solidification effect of sandy soil were studied through sand column test， aqueous solution tests， microscopic observation， and SEM analysis. The experimental results showed that with the increase of the concentration of aluminum chloride additive， the unconfined compressive strength and calcium carbonate production of the samples first increased and then decreased， and the optimal concentration was 6 mmol/L. At this concentration， the strength of the samples increased to 2.8-3.3 times that of the conventional group. Aluminum ions promoted the aggregation of calcium carbonate crystals into a compact structure and regulated the crystal growth rate， thereby improving the uniformity of reinforcement. When calcium acetate was used as the calcium source， calcium carbonate crystals coexisted in the form of lamellar rhombic calcite and needle-like aragonite. Aluminum ions promoted the transformation of metastable vaterite into more stable needle-like aragonite and enhanced the bonding between sand particles， thus optimizing the solidification effect of MICP.
In order to explore the optimization method of solidification performance using microbially induced calcium carbonate precipitation （MICP） technology， a study was conducted based on MICP combined with additive technology， using calcium acetate as the calcium source. The effect and micro-mechanism of aluminum chloride additive on the optimization of MICP solidification effect of sandy soil were studied through sand column test， aqueous solution tests， microscopic observation， and SEM analysis. The experimental results showed that with the increase of the concentration of aluminum chloride additive， the unconfined compressive strength and calcium carbonate production of the samples first increased and then decreased， and the optimal concentration was 6 mmol/L. At this concentration， the strength of the samples increased to 2.8-3.3 times that of the conventional group. Aluminum ions promoted the aggregation of calcium carbonate crystals into a compact structure and regulated the crystal growth rate， thereby improving the uniformity of reinforcement. When calcium acetate was used as the calcium source， calcium carbonate crystals coexisted in the form of lamellar rhombic calcite and needle-like aragonite. Aluminum ions promoted the transformation of metastable vaterite into more stable needle-like aragonite and enhanced the bonding between sand particles， thus optimizing the solidification effect of MICP.
2026, 56(4): 274-284.
doi: 10.3724/j.gyjzG23110212
Abstract:
In order to explore the influence of open holes on the monotonic mechanical properties of Q355B cold-formed high-strength steel plate， 8 groups of test samples were designed for each thickness， using 2 mm and 3 mm thick specimen steel plates， and 3 parallel samples were set up for mechanical test tests in each group. Then the influence of the thickness of the specimen， the number and type of holes on mechanical properties of the specimen were discussed by analyzing the stress-strain curve of the specimen. On this basis， the finite element analysis software was used to create a model of an open-hole specimen. The model was then compared with the results of the material properties test to validate its accuracy and reliability. This process is convenient for subsequent development and research. The test results show that the unopened specimen has an obvious necking phenomenon near the fracture of the open-hole specimen， and the failure and stress concentration phenomenon occur near the hole of the open specimen. Under the premise of the same type of open-hole specimen， the greater the thickness of the specimen， the stronger the capacity of resisting the damage of the open-hole defect； the greater the thickness， the better the mechanical properties such as ductility and energy dissipation capacity； With the increase of the opening diameter， the strength index and deformation ability of the specimen were reduced， but its influence on the elongation was increased； Specimens with hole openings arranged along the direction of external force had a better energy dissipation capacity than specimens with hole openings perpendicular to the direction of external force.
In order to explore the influence of open holes on the monotonic mechanical properties of Q355B cold-formed high-strength steel plate， 8 groups of test samples were designed for each thickness， using 2 mm and 3 mm thick specimen steel plates， and 3 parallel samples were set up for mechanical test tests in each group. Then the influence of the thickness of the specimen， the number and type of holes on mechanical properties of the specimen were discussed by analyzing the stress-strain curve of the specimen. On this basis， the finite element analysis software was used to create a model of an open-hole specimen. The model was then compared with the results of the material properties test to validate its accuracy and reliability. This process is convenient for subsequent development and research. The test results show that the unopened specimen has an obvious necking phenomenon near the fracture of the open-hole specimen， and the failure and stress concentration phenomenon occur near the hole of the open specimen. Under the premise of the same type of open-hole specimen， the greater the thickness of the specimen， the stronger the capacity of resisting the damage of the open-hole defect； the greater the thickness， the better the mechanical properties such as ductility and energy dissipation capacity； With the increase of the opening diameter， the strength index and deformation ability of the specimen were reduced， but its influence on the elongation was increased； Specimens with hole openings arranged along the direction of external force had a better energy dissipation capacity than specimens with hole openings perpendicular to the direction of external force.
2026, 56(4): 285-291.
doi: 10.3724/j.gyjzG24091402
Abstract:
The influence of temperature and edge distance on the shear performance of nine high-strength aluminum alloy plate bolted connections was studied through low-temperature monotonic tensile tests. The results showed that low temperatures did not significantly affect the failure mode of specimens. When the edge distance increased from 1.0d0 to 1.5d0 and 2.0d0， the failure mode changed from net cross-section failure to a mixed failure of end tearing and transverse tearing； the ultimate bearing capacity of the specimen was basically not affected by low temperatures. However， when the edge distance increased from 1.0d0 to 1.5d0， the ultimate bearing capacity of the specimen increased significantly， by about 100%. The experimental results were compared with the calculation results of domestic and international standards. It was found that the American standard can better predict the ultimate bearing capacity of the specimens， while the calculation results of the Chinese and European standards are more conservative when the edge distance is not less than 1.5d0.
The influence of temperature and edge distance on the shear performance of nine high-strength aluminum alloy plate bolted connections was studied through low-temperature monotonic tensile tests. The results showed that low temperatures did not significantly affect the failure mode of specimens. When the edge distance increased from 1.0d0 to 1.5d0 and 2.0d0， the failure mode changed from net cross-section failure to a mixed failure of end tearing and transverse tearing； the ultimate bearing capacity of the specimen was basically not affected by low temperatures. However， when the edge distance increased from 1.0d0 to 1.5d0， the ultimate bearing capacity of the specimen increased significantly， by about 100%. The experimental results were compared with the calculation results of domestic and international standards. It was found that the American standard can better predict the ultimate bearing capacity of the specimens， while the calculation results of the Chinese and European standards are more conservative when the edge distance is not less than 1.5d0.
2026, 56(4): 292-299.
doi: 10.3724/j.gyjzG24060201
Abstract:
With economic development and to meet the needs of social progress， complex steel structures have been widely used in large public buildings such as stadiums， stations， and airports. A mechanical simulation analysis of the construction process was carried out for the complex steel structure project of the Qingdao Virtual Reality and Enjoyment Center. The structure features an inverted conical spatial grid-trussed tube with a steel frame. The characteristics and key techniques involved in the five key construction steps of the complex steel structure project were analyzed. In addition， the grid-tube-truss system was simulated with MIDAS/Gen software during the pre-construction phase. According to the construction scheme， the construction process was mainly divided into 12 steps.The deformation and stress of the structure at each construction step were studied through a mechanical simulation of the entire construction process. The results demonstrated that the structure’s behavior met the limit requirements of Standard for Design of Steel Structures（GB 50017-2017）， thereby providing support for ensuring structural safety during construction. Finally， key and difficult aspects in the construction of the complex steel structure project were analyzed， and corresponding control measures were put forward， wproviding a reference for safe construction.
With economic development and to meet the needs of social progress， complex steel structures have been widely used in large public buildings such as stadiums， stations， and airports. A mechanical simulation analysis of the construction process was carried out for the complex steel structure project of the Qingdao Virtual Reality and Enjoyment Center. The structure features an inverted conical spatial grid-trussed tube with a steel frame. The characteristics and key techniques involved in the five key construction steps of the complex steel structure project were analyzed. In addition， the grid-tube-truss system was simulated with MIDAS/Gen software during the pre-construction phase. According to the construction scheme， the construction process was mainly divided into 12 steps.The deformation and stress of the structure at each construction step were studied through a mechanical simulation of the entire construction process. The results demonstrated that the structure’s behavior met the limit requirements of Standard for Design of Steel Structures（GB 50017-2017）， thereby providing support for ensuring structural safety during construction. Finally， key and difficult aspects in the construction of the complex steel structure project were analyzed， and corresponding control measures were put forward， wproviding a reference for safe construction.
2026, 56(4): 300-308.
doi: 10.3724/j.gyjzG24103103
Abstract:
With the continuous expansion of the power grid scale and the increasing demand for electricity， the load demand of transmission towers continues to rise. Studying the non-destructive reinforcement of their key components is of great theoretical significance and practical value for improving their structural function and extending their service life. Lightweight and high-strength glass-fiber reinforced polyurethane （GRPU） is used to replace steel in traditional reinforcement， and the inclined angle （single-limb angle） commonly used in transmission towers is selected as the research object. A refined finite element model of the single-limb angle before and after reinforcement was established based on the non-destructive double-sided reinforcement scheme. A compression test of the single-limb angle was designed and conducted to verify the accuracy of the finite element simulation， and the effects of the two parameters， namely reinforcement ratio and slenderness ratio. were investigated. The effects of reinforcement ratio and slenderness ratio on the failure mode and bearing capacity of reinforced single-limb angle components were analyzed， and the reinforcement mechanism of the GRPU non-destructive reinforcement scheme was revealed. The results showed that the reinforcement limited the torsional deformation of the components and improved their bending stiffness， thereby enhancing the bearing capacity of the members； with the increase of the slenderness ratio and reinforcement ratio， the reinforcement effect continued to improve. Finally， a reinforcement ratio for single-limb angles was proposed.
With the continuous expansion of the power grid scale and the increasing demand for electricity， the load demand of transmission towers continues to rise. Studying the non-destructive reinforcement of their key components is of great theoretical significance and practical value for improving their structural function and extending their service life. Lightweight and high-strength glass-fiber reinforced polyurethane （GRPU） is used to replace steel in traditional reinforcement， and the inclined angle （single-limb angle） commonly used in transmission towers is selected as the research object. A refined finite element model of the single-limb angle before and after reinforcement was established based on the non-destructive double-sided reinforcement scheme. A compression test of the single-limb angle was designed and conducted to verify the accuracy of the finite element simulation， and the effects of the two parameters， namely reinforcement ratio and slenderness ratio. were investigated. The effects of reinforcement ratio and slenderness ratio on the failure mode and bearing capacity of reinforced single-limb angle components were analyzed， and the reinforcement mechanism of the GRPU non-destructive reinforcement scheme was revealed. The results showed that the reinforcement limited the torsional deformation of the components and improved their bending stiffness， thereby enhancing the bearing capacity of the members； with the increase of the slenderness ratio and reinforcement ratio， the reinforcement effect continued to improve. Finally， a reinforcement ratio for single-limb angles was proposed.
2026, 56(4): 309-318.
doi: 10.3724/j.gyjzG24111501
Abstract:
Rebar corrosion is a leading cause of degradation in reinforced concrete （RC） structures， particularly in coastal environments. This study investigated the corrosion-induced cracking mechanism of concrete cover， focusing on the localized accumulation of corrosion products （rust peaks） at the steel-concrete interface due to inherent defects. Micro-computed tomography （μCT） was employed to perform a non-destructive， three-dimensional analysis of rust peaks forming at the steel-concrete interface. A three-dimensional rust peak fitting model based on a two-dimensional Gaussian function was proposed， and its accuracy was verified with experimental data. Based on this model， the relations between rust peaks and natural interface defects were examined， and a corrosion-induced cracking model for the cover was established. The findings revealed that the crack width increased significantly with the growth of rust peak height， and specimens with thinner concrete cover were more prone to developing distinct cracks. The model demonstrated high prediction accuracy in laboratory testing， with most prediction errors remaining within 15%. These results provide theoretical support for understanding structural degradation induced by rebar corrosion in engineering practice， although their applicability in complex environments still requires further verification.
Rebar corrosion is a leading cause of degradation in reinforced concrete （RC） structures， particularly in coastal environments. This study investigated the corrosion-induced cracking mechanism of concrete cover， focusing on the localized accumulation of corrosion products （rust peaks） at the steel-concrete interface due to inherent defects. Micro-computed tomography （μCT） was employed to perform a non-destructive， three-dimensional analysis of rust peaks forming at the steel-concrete interface. A three-dimensional rust peak fitting model based on a two-dimensional Gaussian function was proposed， and its accuracy was verified with experimental data. Based on this model， the relations between rust peaks and natural interface defects were examined， and a corrosion-induced cracking model for the cover was established. The findings revealed that the crack width increased significantly with the growth of rust peak height， and specimens with thinner concrete cover were more prone to developing distinct cracks. The model demonstrated high prediction accuracy in laboratory testing， with most prediction errors remaining within 15%. These results provide theoretical support for understanding structural degradation induced by rebar corrosion in engineering practice， although their applicability in complex environments still requires further verification.
