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2020 Vol. 50, No. 2
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2020, 50(2): 1-9,23.
doi: 10.13204/j.gyjz202002001
Abstract:
The structure of stainless steel sandwich panel is a new type of prefabricated structural system. In order to reveal the compression properties of core tubes for the structure of stainless steel sandwich panel, a total of 12 sets of specimens which included 212 components were manufactured, and the compression strengths and compression moduli of the core tubes for the structure of stainless steel sandwich panel were obtained. Then the finite element analysis was used to simulate the test process, and the comparison of finite element calculation results the experimental results were in good agreement, which could verify the accuracy of the finite element method. And the theoretical analysis of the compression properties for core tubes was carried out. The research showed that the stress process of core tubes for the structure of stainless steel sandwich panel could be divided into three stages:elastic stage, elastic-plastic stage and failure stage, and it was found that the essence of core tube damage was the local buckling failure at the end of the core tube. Finally, the theoretical calculation formula for the compression strength design value of core tubes for the structure of stainless steel sandwich panel was given.
The structure of stainless steel sandwich panel is a new type of prefabricated structural system. In order to reveal the compression properties of core tubes for the structure of stainless steel sandwich panel, a total of 12 sets of specimens which included 212 components were manufactured, and the compression strengths and compression moduli of the core tubes for the structure of stainless steel sandwich panel were obtained. Then the finite element analysis was used to simulate the test process, and the comparison of finite element calculation results the experimental results were in good agreement, which could verify the accuracy of the finite element method. And the theoretical analysis of the compression properties for core tubes was carried out. The research showed that the stress process of core tubes for the structure of stainless steel sandwich panel could be divided into three stages:elastic stage, elastic-plastic stage and failure stage, and it was found that the essence of core tube damage was the local buckling failure at the end of the core tube. Finally, the theoretical calculation formula for the compression strength design value of core tubes for the structure of stainless steel sandwich panel was given.
2020, 50(2): 10-16.
doi: 10.13204/j.gyjz202002002
Abstract:
In order to study the shear properties of core tubes for the structure of stainless steel sandwich panel, experimental studies and finite element simulations were conducted on multiple sets of stainless steel sandwich panel specimens, and the results of the two were compared to verify the accuracy of the finite element models. On this basis, the cutting process and failure mechanism of core tubes were analyzed. The research showed that the bearing process of core tubes for the structure of stainless steel sandwich panel under shearing force could be divided into three stages:elastic force stage, elastoplastic force stage and plastic failure stage; the essence of core tube damage was local buckling failure in the compression zone caused by bending at the end of core tubes.
In order to study the shear properties of core tubes for the structure of stainless steel sandwich panel, experimental studies and finite element simulations were conducted on multiple sets of stainless steel sandwich panel specimens, and the results of the two were compared to verify the accuracy of the finite element models. On this basis, the cutting process and failure mechanism of core tubes were analyzed. The research showed that the bearing process of core tubes for the structure of stainless steel sandwich panel under shearing force could be divided into three stages:elastic force stage, elastoplastic force stage and plastic failure stage; the essence of core tube damage was local buckling failure in the compression zone caused by bending at the end of core tubes.
2020, 50(2): 17-23.
doi: 10.13204/j.gyjz202002003
Abstract:
The lateral compressive performance for the structure of stainless steel sandwich panel was studied and analyzed theoretically. The effects of panel thickness, the wall thickness and spacing of core tube on the lateral compressive performance of the structure were mainly discussed. The experimental research showed that the specimens designed by different parameters mainly included three types of damage forms:local wrinkle instability, overall buckling instability, and local buckling instability, and they were respectively related to the longitudinal spacing of the core tube, the shear modulus and the flatwise compression modulus of the sandwich core. When the first two failure modes occurred, the ultimate displacement of the specimen and the ultimate stress of the panel were small, and the ductility was poor; when the local buckling instability occurred, the ultimate displacement of the specimen and the ultimate stress of the panel were large, and the ductility was good. In order to avoid the local wrinkle instability and the overall buckling instability under structural lateral pressure action, the measures to reduce the longitudinal spacing of the core tube and increase the shear modulus of the core were suggested.
The lateral compressive performance for the structure of stainless steel sandwich panel was studied and analyzed theoretically. The effects of panel thickness, the wall thickness and spacing of core tube on the lateral compressive performance of the structure were mainly discussed. The experimental research showed that the specimens designed by different parameters mainly included three types of damage forms:local wrinkle instability, overall buckling instability, and local buckling instability, and they were respectively related to the longitudinal spacing of the core tube, the shear modulus and the flatwise compression modulus of the sandwich core. When the first two failure modes occurred, the ultimate displacement of the specimen and the ultimate stress of the panel were small, and the ductility was poor; when the local buckling instability occurred, the ultimate displacement of the specimen and the ultimate stress of the panel were large, and the ductility was good. In order to avoid the local wrinkle instability and the overall buckling instability under structural lateral pressure action, the measures to reduce the longitudinal spacing of the core tube and increase the shear modulus of the core were suggested.
2020, 50(2): 24-33,58.
doi: 10.13204/j.gyjz202002004
Abstract:
The structure of stainless steel sandwich panel is a new type of building structure system similar to the honeycomb plate. The structure is formed by brazing a thin-walled pipe arranged at a certain distance between the upper and lower panels. In the paper, the deflections at the mid-span of four-side simply supported unidirectional plates of the structure of stainless steel sandwich panel were studied by experiments, finite element analysis and theoretical analysis. Theoretical analysis was based on the principle of virtual work. Through the simplification of the mechanical model of stainless steel sandwich panel, the formula for calculating the deflection of the four-side simply supported unidirectional plate with the structure of stainless steel sandwich panel subjected to concentrated load at the mid-span was derived. Through the test results, the deflection calculation formula was verified. Finally, the influence of different parameters on the deflection of the four-side unidirectional plate of stainless steel sandwich panel was analyzed. The research results showed that the deflection calculation formula based on the virtual work principle could accurately calculate the mid-span deflection of the four-side simply supported unidirectional plate of the structure of stainless steel sandwich panel. In addition, the outer diameter of the core tube, the longitudinal spacing, and the thickness of the panel had a greater impact on the mid-span deflection.
The structure of stainless steel sandwich panel is a new type of building structure system similar to the honeycomb plate. The structure is formed by brazing a thin-walled pipe arranged at a certain distance between the upper and lower panels. In the paper, the deflections at the mid-span of four-side simply supported unidirectional plates of the structure of stainless steel sandwich panel were studied by experiments, finite element analysis and theoretical analysis. Theoretical analysis was based on the principle of virtual work. Through the simplification of the mechanical model of stainless steel sandwich panel, the formula for calculating the deflection of the four-side simply supported unidirectional plate with the structure of stainless steel sandwich panel subjected to concentrated load at the mid-span was derived. Through the test results, the deflection calculation formula was verified. Finally, the influence of different parameters on the deflection of the four-side unidirectional plate of stainless steel sandwich panel was analyzed. The research results showed that the deflection calculation formula based on the virtual work principle could accurately calculate the mid-span deflection of the four-side simply supported unidirectional plate of the structure of stainless steel sandwich panel. In addition, the outer diameter of the core tube, the longitudinal spacing, and the thickness of the panel had a greater impact on the mid-span deflection.
2020, 50(2): 34-39.
doi: 10.13204/j.gyjz202002005
Abstract:
ABAQUS finite element software was used in numerical simulation to study the three-point bend properties of the stainless steel sandwich panel with core tubes, and explore the factors that influenced its failure mode and bending performance. The results showed that the bending curve of stainless steel sandwich panel under three-point load could be divided into three stages:elastic stage, elastoplastic stage and failure stage; and the main failure mode of stainless steel sandwich panel with core tubes was divided into shear failure at core tube end, the overall bending damage and the panel shear failure; the ultimate bearing capacity of the panel under three-point load was affected by the panel thickness, the wall thickness of the core tube and the diameter of the core tube.
ABAQUS finite element software was used in numerical simulation to study the three-point bend properties of the stainless steel sandwich panel with core tubes, and explore the factors that influenced its failure mode and bending performance. The results showed that the bending curve of stainless steel sandwich panel under three-point load could be divided into three stages:elastic stage, elastoplastic stage and failure stage; and the main failure mode of stainless steel sandwich panel with core tubes was divided into shear failure at core tube end, the overall bending damage and the panel shear failure; the ultimate bearing capacity of the panel under three-point load was affected by the panel thickness, the wall thickness of the core tube and the diameter of the core tube.
2020, 50(2): 40-44,50.
doi: 10.13204/j.gyjz202002006
Abstract:
The L-shaped column made of stainless steel sandwich panel with core tubes is a new type of special-shaped column, which makes full use of the advantages of sandwich structure and stainless steel. In this paper, the influence of the panel thickness, the wall thickness of core tube and the spacing of the core tube on the stability of the L-shaped column was studied. The finite element software ABAQUS was used to establish the finite element model and simulate its axial compression performance. The eigenvalue buckling analysis and nonlinear buckling analysis were carried out respectively. The buckling mode, deformation and loading-displacement curve under single sectional parameter change were analyzed. The research showed that the buckling mode of the L-shaped column was flexural buckling, and its failure mode was local buckling failure. With the increase of the panel thickness, the constraint of the core tubes to the panel became weaker and weaker, and the contribution to the stability became smaller and smaller. At the same time, it was found that the influence of the wall thickness of the core tube and the spacing of the core tube on the stability was obvious.
The L-shaped column made of stainless steel sandwich panel with core tubes is a new type of special-shaped column, which makes full use of the advantages of sandwich structure and stainless steel. In this paper, the influence of the panel thickness, the wall thickness of core tube and the spacing of the core tube on the stability of the L-shaped column was studied. The finite element software ABAQUS was used to establish the finite element model and simulate its axial compression performance. The eigenvalue buckling analysis and nonlinear buckling analysis were carried out respectively. The buckling mode, deformation and loading-displacement curve under single sectional parameter change were analyzed. The research showed that the buckling mode of the L-shaped column was flexural buckling, and its failure mode was local buckling failure. With the increase of the panel thickness, the constraint of the core tubes to the panel became weaker and weaker, and the contribution to the stability became smaller and smaller. At the same time, it was found that the influence of the wall thickness of the core tube and the spacing of the core tube on the stability was obvious.
2020, 50(2): 45-50.
doi: 10.13204/j.gyjz202002007
Abstract:
In order to study the effect of sectional height and thickness of column leg for the stainless steel panel with core tubes and the wall thickness of core tube on the T-shaped column under axial compression, combined with the lateral compression performances measured by test, the T-shaped column was analyzed by the finite element analysis software ABAQUS, and the nonlinear buckling was analyzed. The results showed that the buckling mode of the T-shaped column was local buckling of the panel.The length of legs had great influence on the stable bearing capacity.With the increase of thickness of panel,the constraint of core tubes was weaker and weaker,and the contribution to the panel stability was less and less.The core tube could provide support to the panel, but the tubular wall thickness did not play a significant role in the improvement of the stability when the thickness of column leg reached a certain extent.
In order to study the effect of sectional height and thickness of column leg for the stainless steel panel with core tubes and the wall thickness of core tube on the T-shaped column under axial compression, combined with the lateral compression performances measured by test, the T-shaped column was analyzed by the finite element analysis software ABAQUS, and the nonlinear buckling was analyzed. The results showed that the buckling mode of the T-shaped column was local buckling of the panel.The length of legs had great influence on the stable bearing capacity.With the increase of thickness of panel,the constraint of core tubes was weaker and weaker,and the contribution to the panel stability was less and less.The core tube could provide support to the panel, but the tubular wall thickness did not play a significant role in the improvement of the stability when the thickness of column leg reached a certain extent.
2020, 50(2): 51-58.
doi: 10.13204/j.gyjz202002008
Abstract:
The in-line wall of the structure of stainless steel sandwich panel is a cross-shaped member composed of two stainless steel panels and orthogonally arranged stainless steel core tube. The connection between the core tube and the panel is brazed by copper. In the paper, the bearing capacity of in-line wall of stainless steel sandwich panel under axial compression was studied, and the calculation formula of the bearing capacity under axial compression was proposed. Firstly, the finite element eigenvalue buckling analysis was carried out, and the formula for calculating the elastic buckling load of the wall and the corresponding regularized aspect ratio λn was obtained. Through the finite element non-linear analysis, the influence of the thickness of the panel, the aspect ratio, the outer diameter of the core tube, the wall thickness of the core tube and the distribution distance of the core tube on the bearing capacity of the axially compressed in-line wall of stainless steel sandwich panel was analyzed, and the stability coefficient φ of the axial compression was obtained, as well as φ-λn curve of stability by design; three sets of the in-line wall of specimens stainless steel sandwich panel were designed, and the axial compressive bearing capacity was tested. The test results, finite element analysis results and design formulas were in good agreement. The safety of the calculation formula for the axial compressive bearing capacity of the in-line wall of the structure of stainless steel sandwich panel were verified.
The in-line wall of the structure of stainless steel sandwich panel is a cross-shaped member composed of two stainless steel panels and orthogonally arranged stainless steel core tube. The connection between the core tube and the panel is brazed by copper. In the paper, the bearing capacity of in-line wall of stainless steel sandwich panel under axial compression was studied, and the calculation formula of the bearing capacity under axial compression was proposed. Firstly, the finite element eigenvalue buckling analysis was carried out, and the formula for calculating the elastic buckling load of the wall and the corresponding regularized aspect ratio λn was obtained. Through the finite element non-linear analysis, the influence of the thickness of the panel, the aspect ratio, the outer diameter of the core tube, the wall thickness of the core tube and the distribution distance of the core tube on the bearing capacity of the axially compressed in-line wall of stainless steel sandwich panel was analyzed, and the stability coefficient φ of the axial compression was obtained, as well as φ-λn curve of stability by design; three sets of the in-line wall of specimens stainless steel sandwich panel were designed, and the axial compressive bearing capacity was tested. The test results, finite element analysis results and design formulas were in good agreement. The safety of the calculation formula for the axial compressive bearing capacity of the in-line wall of the structure of stainless steel sandwich panel were verified.
2020, 50(2): 59-68.
doi: 10.13204/j.gyjz202002009
Abstract:
The in-line wall of the structure of stainless steel sandwich panel is composed of two stainless steel panels and orthogonally arranged stainless steel core tubes. The connection between the core tube and the panel was brazed by copper. In the paper, the stability of the in-line wall of the structure of stainless steel sandwich panel under compression and bending was studied.Firstly, the finite element eigenvalue buckling analysis was carried out, and the formula for calculating the elastic buckling load of the in-line wall and the corresponding regularized aspect ratio λn was obtained. The finite element nonlinear analysis was used to study the stress process and failure mechanism. The influence of parameters such as aspect ratio, panel thickness, outer diameter of core tube, wall thickness of core tube and distribution distance of core tubes on the stability bearing capacity of the in-line wall of the structure of stainless steel sandwich panel was obtained, as well as the stability coefficient of axial compression φN and pure bending stability coefficient φM, and the φN -λn and φM-λn curves for stable design were established. Based on the reliable finite element method of in-line wall of stainless steel sandwich panel were designed, and the stability bearing capacity under compression and bending was studied by finite element simulation. The results showed that the design formula could calculate the bearing capacity of the component safely.
The in-line wall of the structure of stainless steel sandwich panel is composed of two stainless steel panels and orthogonally arranged stainless steel core tubes. The connection between the core tube and the panel was brazed by copper. In the paper, the stability of the in-line wall of the structure of stainless steel sandwich panel under compression and bending was studied.Firstly, the finite element eigenvalue buckling analysis was carried out, and the formula for calculating the elastic buckling load of the in-line wall and the corresponding regularized aspect ratio λn was obtained. The finite element nonlinear analysis was used to study the stress process and failure mechanism. The influence of parameters such as aspect ratio, panel thickness, outer diameter of core tube, wall thickness of core tube and distribution distance of core tubes on the stability bearing capacity of the in-line wall of the structure of stainless steel sandwich panel was obtained, as well as the stability coefficient of axial compression φN and pure bending stability coefficient φM, and the φN -λn and φM-λn curves for stable design were established. Based on the reliable finite element method of in-line wall of stainless steel sandwich panel were designed, and the stability bearing capacity under compression and bending was studied by finite element simulation. The results showed that the design formula could calculate the bearing capacity of the component safely.
2020, 50(2): 69-75,88.
doi: 10.13204/j.gyjz202002010
Abstract:
Study of time-spatial evolution based on self-organization theory can extract and reveal the internal order and the law of development which is organic renewal must be clear first, and guide the implementation direction and strategy of spatial intervention. On the basis of the explanation of the connotation of self-organization concept, this paper clarify the research sequence of self-organized time-spatial evolution, and interpret the complexity of urban-rural green space system as self-organizing system. Through the analysis of self-creation and maintenance, self-expansion and self-evolution of urban-rural green space system, it explained the mechanism of self-organization time-spatial evolution, including the dynamic mechanism of competition and coordination, the order parameter as the dominating factor, the time-spatial order of dissipative structure and the spatial agglomeration of green attractor, then pointed out that spatial intervention should conform to and promote these key points, so as to achieve the coordination of subjective planning decision-making and objective self-organization laws, and promoted the spiral upward process of the time-spatial evolution of urban-rural green space system.
Study of time-spatial evolution based on self-organization theory can extract and reveal the internal order and the law of development which is organic renewal must be clear first, and guide the implementation direction and strategy of spatial intervention. On the basis of the explanation of the connotation of self-organization concept, this paper clarify the research sequence of self-organized time-spatial evolution, and interpret the complexity of urban-rural green space system as self-organizing system. Through the analysis of self-creation and maintenance, self-expansion and self-evolution of urban-rural green space system, it explained the mechanism of self-organization time-spatial evolution, including the dynamic mechanism of competition and coordination, the order parameter as the dominating factor, the time-spatial order of dissipative structure and the spatial agglomeration of green attractor, then pointed out that spatial intervention should conform to and promote these key points, so as to achieve the coordination of subjective planning decision-making and objective self-organization laws, and promoted the spiral upward process of the time-spatial evolution of urban-rural green space system.
2020, 50(2): 76-81.
doi: 10.13204/j.gyjz202002011
Abstract:
"Small block" is the block space form of low carbon ecological city. Firstly, it analyzed not only the origination of small block idea but also its road grid characteristics; block scale and public transportation form which adapted to the low carbon urban construction. Then, the urban design concept of Tingjiao area of Nansha is expounded with the local feature of Lingnan Shanshui. Building the space structure based on the small block, the project shows characteristics on open space, hill and water landscape and transport system, which provides practical case for urban design that highlight the characteristics of small block.
"Small block" is the block space form of low carbon ecological city. Firstly, it analyzed not only the origination of small block idea but also its road grid characteristics; block scale and public transportation form which adapted to the low carbon urban construction. Then, the urban design concept of Tingjiao area of Nansha is expounded with the local feature of Lingnan Shanshui. Building the space structure based on the small block, the project shows characteristics on open space, hill and water landscape and transport system, which provides practical case for urban design that highlight the characteristics of small block.
2020, 50(2): 89-97.
doi: 10.13204/j.gyjz202002013
Abstract:
Taking Xi'an Textile City Industrial Community as an example to explore the innovative design of service facilities in the community pension environment under the micro-intervention of space environment. Firstly, according to the current situation, the spatial planning model of the old-age environment of the industrial community is explored, and the feasibility development strategy is sought. Secondly, through the bottom-up micro-intervention, the node intervention strategy is proposed to make the residents create regional environmental identity. Finally, through the top-down overall design, the node intervention is systematically and diversified to realize the spatial activation of the environment. Construct a community serial design and service system based on the unique industrial culture value of the region. The regional industrial culture and the renewal of the old-age facilities in the industrial community depend on their complementary and linkageal relationship. The cultural heritage of the unique value of the region is used as a symbol. Through the selection and systematic design of the elements, the collective memory of the elderly residents in the industrial community is created. Regional cultural identity and national cultural self-confidence have a positive role to play.
Taking Xi'an Textile City Industrial Community as an example to explore the innovative design of service facilities in the community pension environment under the micro-intervention of space environment. Firstly, according to the current situation, the spatial planning model of the old-age environment of the industrial community is explored, and the feasibility development strategy is sought. Secondly, through the bottom-up micro-intervention, the node intervention strategy is proposed to make the residents create regional environmental identity. Finally, through the top-down overall design, the node intervention is systematically and diversified to realize the spatial activation of the environment. Construct a community serial design and service system based on the unique industrial culture value of the region. The regional industrial culture and the renewal of the old-age facilities in the industrial community depend on their complementary and linkageal relationship. The cultural heritage of the unique value of the region is used as a symbol. Through the selection and systematic design of the elements, the collective memory of the elderly residents in the industrial community is created. Regional cultural identity and national cultural self-confidence have a positive role to play.
2020, 50(2): 104-108,112.
doi: 10.13204/j.gyjz202002015
Abstract:
A building was chosen to conduct pushover analysis in order to study the effect of carbon fiber reinforced polymer (CFRP) on the seismic behavior of concrete frame structures. Two CFRP reinforcement schemes were designed for an existing eight-story frame structure office building in accordance with China's "Code for Design of Concrete Structure Reinforcement (GB 50367-2013)." One was local seismic reinforcement, the other was integral seismic reinforcement. The finite element analysis software is used to establish the common frame structure and the structural model under two different reinforcement schemes, and modal analysis and pushover analysis were carried out on the three models respectively. From the aspects of stiffness variation and displacement response of the structure, the seismic beharior before and after structural reinforcement was evaluated. It was found that the self-vibration frequency of the structure increased after reinforcement, which indicates that the CFRP could enhance the stiffness of the structure to some extent, but the first three main mode frequencies only increased less than 5%; Under the same deformation, the base shear force of scheme 1 increased by 24.5% compared with the initial structure, and the base shear force of scheme 2 increased by 30.4%, indicating that the structure can withstand greater deformation after CFRP reinforcement, so the ductihty is greatly improved. The floor displacement and story drift angle showed decreasing trends, the maximum story drift angle of the first scheme was reduced by 3.8%, the maximum story drift angle of the second scheme was reduced by 20%. The analysis showed that CFRP could effectively improve the seismic behavior of concrete frame structure, and the core performance was the improvement of ductility of the structure; in order to ensure the safety of the structure, the structure should be reinforced integrally.
A building was chosen to conduct pushover analysis in order to study the effect of carbon fiber reinforced polymer (CFRP) on the seismic behavior of concrete frame structures. Two CFRP reinforcement schemes were designed for an existing eight-story frame structure office building in accordance with China's "Code for Design of Concrete Structure Reinforcement (GB 50367-2013)." One was local seismic reinforcement, the other was integral seismic reinforcement. The finite element analysis software is used to establish the common frame structure and the structural model under two different reinforcement schemes, and modal analysis and pushover analysis were carried out on the three models respectively. From the aspects of stiffness variation and displacement response of the structure, the seismic beharior before and after structural reinforcement was evaluated. It was found that the self-vibration frequency of the structure increased after reinforcement, which indicates that the CFRP could enhance the stiffness of the structure to some extent, but the first three main mode frequencies only increased less than 5%; Under the same deformation, the base shear force of scheme 1 increased by 24.5% compared with the initial structure, and the base shear force of scheme 2 increased by 30.4%, indicating that the structure can withstand greater deformation after CFRP reinforcement, so the ductihty is greatly improved. The floor displacement and story drift angle showed decreasing trends, the maximum story drift angle of the first scheme was reduced by 3.8%, the maximum story drift angle of the second scheme was reduced by 20%. The analysis showed that CFRP could effectively improve the seismic behavior of concrete frame structure, and the core performance was the improvement of ductility of the structure; in order to ensure the safety of the structure, the structure should be reinforced integrally.
2020, 50(2): 109-112.
doi: 10.13204/j.gyjz202002016
Abstract:
A series of unconfined compression tests were conducted on a riverbed silt improved with basalt fibers ordinary Portland cement. Basalt fibers of length 3, 6, 12, 20 mm and 35 mm were used in the study with different fiber contents of 0%, 0.1%, 0.3%, 0.5%, and 0.7% by weight of soil. To study the effect of curing time on strength, the specimens were cured for 7, 14, and 28 days and tested. The test results showed that the basalt fiber could effectively improve the resistance to deformation of cement-stabilized soil. The unconfined compressive strength of fiber-cement soil increased with increasing curing time. For constant fiber length, the unconfined compressive strength of fiber-cement soil increases with increasing fiber content. However, for constant fiber content, the unconfined compressive strength of fiber-cement soil did not change significantly with the increase of fiber length.
A series of unconfined compression tests were conducted on a riverbed silt improved with basalt fibers ordinary Portland cement. Basalt fibers of length 3, 6, 12, 20 mm and 35 mm were used in the study with different fiber contents of 0%, 0.1%, 0.3%, 0.5%, and 0.7% by weight of soil. To study the effect of curing time on strength, the specimens were cured for 7, 14, and 28 days and tested. The test results showed that the basalt fiber could effectively improve the resistance to deformation of cement-stabilized soil. The unconfined compressive strength of fiber-cement soil increased with increasing curing time. For constant fiber length, the unconfined compressive strength of fiber-cement soil increases with increasing fiber content. However, for constant fiber content, the unconfined compressive strength of fiber-cement soil did not change significantly with the increase of fiber length.
2020, 50(2): 113-118,149.
doi: 10.13204/j.gyjz202002017
Abstract:
To study the correlations of influence factors between strength and durability for lightweight aggregate concrete (LWAC), a serial of tests on compressive strength, carbonization depth, chloride ion penetration and sulfate attack were carried out. Where the tested concretes include all-lightweight shale ceramsite concrete (ALWSCC), ALWSCC replaced part of fly ash with limestone powder (LSP) in equal mass, chopped basalt fibers (CBF) reinforced ALWSCC, the LWCSFA, LWCSCA and HLWC made from ALWSCC replaced shale pottery and shale ceramsite with river sand and normal coarse aggregates in equal volume and in single or double methods accordingly, respectively, and the corresponding self-compacting LWACs (SCLWCSFA, SCLWCSCA and SCHLWC). The results showed that the durability indexes of different kinds of LWACs were closely related to concrete type and strength grade, but the strength indexes were out of step with the durability indexes. The LSP, CBF and normal weight aggregates could effectively improve the carbonation resistance of LWACs, and the self-compacting LWACs were better. The modified carbonization model of normal weight concrete (NWC) was suitable for LWAC. The quantity of electric charge through LWACs showed a great differences at 28 d, but it was significantly reduced and approached at 56 d, and the resistance chloride ion permeability of CBF reinforced ALWSCC and SCLWCSFA were better. The loss rates of compressive strength (k) and corrosion resistance coefficients (Kf) of different kinds of LWACs were similar, respectively, and which exhibited synchronism and strong correlation under the same dry-wet cycle times. However, only the k and Kf of self-compacting LWACs increased first and then decreased with the increase of dry-wet cycle times.
To study the correlations of influence factors between strength and durability for lightweight aggregate concrete (LWAC), a serial of tests on compressive strength, carbonization depth, chloride ion penetration and sulfate attack were carried out. Where the tested concretes include all-lightweight shale ceramsite concrete (ALWSCC), ALWSCC replaced part of fly ash with limestone powder (LSP) in equal mass, chopped basalt fibers (CBF) reinforced ALWSCC, the LWCSFA, LWCSCA and HLWC made from ALWSCC replaced shale pottery and shale ceramsite with river sand and normal coarse aggregates in equal volume and in single or double methods accordingly, respectively, and the corresponding self-compacting LWACs (SCLWCSFA, SCLWCSCA and SCHLWC). The results showed that the durability indexes of different kinds of LWACs were closely related to concrete type and strength grade, but the strength indexes were out of step with the durability indexes. The LSP, CBF and normal weight aggregates could effectively improve the carbonation resistance of LWACs, and the self-compacting LWACs were better. The modified carbonization model of normal weight concrete (NWC) was suitable for LWAC. The quantity of electric charge through LWACs showed a great differences at 28 d, but it was significantly reduced and approached at 56 d, and the resistance chloride ion permeability of CBF reinforced ALWSCC and SCLWCSFA were better. The loss rates of compressive strength (k) and corrosion resistance coefficients (Kf) of different kinds of LWACs were similar, respectively, and which exhibited synchronism and strong correlation under the same dry-wet cycle times. However, only the k and Kf of self-compacting LWACs increased first and then decreased with the increase of dry-wet cycle times.
2020, 50(2): 119-123.
doi: 10.13204/j.gyjz202002018
Abstract:
In the paper, nano-clay (NC) was used to modify the properties of cementitious system with high-volume fly ash (FA) to overcome the disadvantage of low strength. The effects of NC content (0.6%~1.0%), water-binder ratio (0.4, 0.45, 0.5), and fly ash (FA) content (50%~70%) on the fluidity, compressive strength and flexural strength of the cementitious system with high-volume fly ash were studied. The results showed that the more content of FA, the higher fluidity of the system, and the lower compressive strength and flexural strength. The incorporation of NC resulted in a decrease in the fluidity of the FA cementitious system, and the more content of NC, the lower the fluidity with the decreasing range between 13.0% and 29.6%. NC could significantly improve the compressive strength of high-volume FA cementitious system within 28 days, which was between 37.5% and 49.5%. For the high-volume FA cementitious system with 60% FA, the highest compressive strength was obtained with 0.6% NC. Meanwhile, the NC increased the flexural strength of the FA cementitious system by between 15% and 20%.
In the paper, nano-clay (NC) was used to modify the properties of cementitious system with high-volume fly ash (FA) to overcome the disadvantage of low strength. The effects of NC content (0.6%~1.0%), water-binder ratio (0.4, 0.45, 0.5), and fly ash (FA) content (50%~70%) on the fluidity, compressive strength and flexural strength of the cementitious system with high-volume fly ash were studied. The results showed that the more content of FA, the higher fluidity of the system, and the lower compressive strength and flexural strength. The incorporation of NC resulted in a decrease in the fluidity of the FA cementitious system, and the more content of NC, the lower the fluidity with the decreasing range between 13.0% and 29.6%. NC could significantly improve the compressive strength of high-volume FA cementitious system within 28 days, which was between 37.5% and 49.5%. For the high-volume FA cementitious system with 60% FA, the highest compressive strength was obtained with 0.6% NC. Meanwhile, the NC increased the flexural strength of the FA cementitious system by between 15% and 20%.
2020, 50(2): 124-129.
doi: 10.13204/j.gyjz202002019
Abstract:
The application status of anchor channels in prefabricated construction projects was discussed, and the influence of installation performance on engineering quality was expounded. Through the designed experiments, the relation between installation torque and reaction force, the relations between installation torque and the minimum margin and thickness of the concrete base, the influence factors of parallel shear were studied by the quantitative analysis. By adopting the statistical method for processing test results, some suggestions wer presented for improving the anchor performance of anchor channels, in order that the performance of the anchorage system could be more reasonably applied in the prefabricated construction projects.
The application status of anchor channels in prefabricated construction projects was discussed, and the influence of installation performance on engineering quality was expounded. Through the designed experiments, the relation between installation torque and reaction force, the relations between installation torque and the minimum margin and thickness of the concrete base, the influence factors of parallel shear were studied by the quantitative analysis. By adopting the statistical method for processing test results, some suggestions wer presented for improving the anchor performance of anchor channels, in order that the performance of the anchorage system could be more reasonably applied in the prefabricated construction projects.
2020, 50(2): 130-136.
doi: 10.13204/j.gyjz202002020
Abstract:
Radome not only provides independent and closed space for radar to ensure the safe operation of radar, but it also radome provides "transparent" transmitting and receiving electromagnetic window for antenna to ensure normal and reliable operation of radar. Therefore, the research of the mechanical properties of the radome is of great significance to the safety of the radome itself and the safety of its internal radar equipment.Block metal frames radome is a typical single-layer lattice shell structure, based on FEA, the mechanical properties analysis flow of block metal frames radome with flexible skin was elaboratedin in this paper. Taking a metal frames radome which the diameter is 28.5 m as an example, the form-finding, statics, dynamics and stability analysis are carried out. On this basis, the diaphragm effect of flexible skin on the mechanical properties of radome was studied experimentally.The analysis results showed that the radome could meet the requirements of structural stiffness and strength under the most stringent load conditions,and the design was safe and reliable. At the same time, the experimental results showed that the diaphragm effect of the radome was obvious, which could significantly improve the overall bearing capacity of the radome and further improve the safety of the structure of radome.
Radome not only provides independent and closed space for radar to ensure the safe operation of radar, but it also radome provides "transparent" transmitting and receiving electromagnetic window for antenna to ensure normal and reliable operation of radar. Therefore, the research of the mechanical properties of the radome is of great significance to the safety of the radome itself and the safety of its internal radar equipment.Block metal frames radome is a typical single-layer lattice shell structure, based on FEA, the mechanical properties analysis flow of block metal frames radome with flexible skin was elaboratedin in this paper. Taking a metal frames radome which the diameter is 28.5 m as an example, the form-finding, statics, dynamics and stability analysis are carried out. On this basis, the diaphragm effect of flexible skin on the mechanical properties of radome was studied experimentally.The analysis results showed that the radome could meet the requirements of structural stiffness and strength under the most stringent load conditions,and the design was safe and reliable. At the same time, the experimental results showed that the diaphragm effect of the radome was obvious, which could significantly improve the overall bearing capacity of the radome and further improve the safety of the structure of radome.
2020, 50(2): 137-142,157.
doi: 10.13204/j.gyjz202002021
Abstract:
With the rapid development of technologies, performance of material and structures can be greatly improved through tools such as topological optimization, 3D printing and laser cutting. In the paper, a negative Poisson's ratio steel plate consisting of repeated cross-arranged of concave hexagonal elements was designed, which could control the longitudinal height and lateral thickness of the concave hexagon to a constant value and increase the energy consumption if the stiffness satisfied the axial force and the cross-sectional area. Based on the response surface method, the parameters were optimized by controlling different parameters to maximize the energy dissipation. Through the above process, the optimized design of the entire negative Poisson's ratio structure was completed. The results showed that the concave hexagonal unit size had the largest energy dissipation when the concave angle (α)=24.73°, the ratio of the longitudinal direction to the transverse unit length, h/l, equaled to 0.7, and the ratio of the transverse to the longitudinal unit thickness, b1/b2, equaled to 10 under the constraint condition.
With the rapid development of technologies, performance of material and structures can be greatly improved through tools such as topological optimization, 3D printing and laser cutting. In the paper, a negative Poisson's ratio steel plate consisting of repeated cross-arranged of concave hexagonal elements was designed, which could control the longitudinal height and lateral thickness of the concave hexagon to a constant value and increase the energy consumption if the stiffness satisfied the axial force and the cross-sectional area. Based on the response surface method, the parameters were optimized by controlling different parameters to maximize the energy dissipation. Through the above process, the optimized design of the entire negative Poisson's ratio structure was completed. The results showed that the concave hexagonal unit size had the largest energy dissipation when the concave angle (α)=24.73°, the ratio of the longitudinal direction to the transverse unit length, h/l, equaled to 0.7, and the ratio of the transverse to the longitudinal unit thickness, b1/b2, equaled to 10 under the constraint condition.
2020, 50(2): 143-149.
doi: 10.13204/j.gyjz202002022
Abstract:
In order to study the mechanical properties of thin-walled stainless steel tube composite short columns filled with steel-reinforced concrete, six concrete filled thin-walled stainless steel tube composite short columns were designed, including four stainless steel tube composite columns filled with steel-reinforced concrete and two concrete filled stainless steel tube stub columns for comparison. The failure modes, load-displacement curves, bearing capacity and strain characteristics of each specimen were analyzed by the results of axial compression performance test of stainless steel pipe composite short columns. The effects of different variables on the ultimate bearing capacity and residual bearing capacity were studied. The test results showed that stainless steel tube composite short columns filled with steel-reinforced concrete had higher bearing capacity and better ductility. The steel ratio had a great influence on the ultimate bearing capacity. The ultimate bearing capacity of specimens was improved significantly with the increase of steel ratio and concrete strength. The test results of bearing capacity were compared with the predicted bearing capacity using the Eurocode 4, GB 50936 and the proposed formula by related scholars. The formula considering the dual confinement effect of steel tube and section steel could predict accurately the bearing capacity of stainless steel tube composite short column filled with steel-reinforced concrete.
In order to study the mechanical properties of thin-walled stainless steel tube composite short columns filled with steel-reinforced concrete, six concrete filled thin-walled stainless steel tube composite short columns were designed, including four stainless steel tube composite columns filled with steel-reinforced concrete and two concrete filled stainless steel tube stub columns for comparison. The failure modes, load-displacement curves, bearing capacity and strain characteristics of each specimen were analyzed by the results of axial compression performance test of stainless steel pipe composite short columns. The effects of different variables on the ultimate bearing capacity and residual bearing capacity were studied. The test results showed that stainless steel tube composite short columns filled with steel-reinforced concrete had higher bearing capacity and better ductility. The steel ratio had a great influence on the ultimate bearing capacity. The ultimate bearing capacity of specimens was improved significantly with the increase of steel ratio and concrete strength. The test results of bearing capacity were compared with the predicted bearing capacity using the Eurocode 4, GB 50936 and the proposed formula by related scholars. The formula considering the dual confinement effect of steel tube and section steel could predict accurately the bearing capacity of stainless steel tube composite short column filled with steel-reinforced concrete.
2020, 50(2): 150-157.
doi: 10.13204/j.gyjz202002023
Abstract:
In order to study the difference of axial compression properties of recycled concrete filled square(RCFSST) and circular steel tube (RCFCST) short column after being subjected to high temperatures and water cooling, 27 RCFSST and 27 RCFCST short columns were designed for axial compression test, with the variable parameters of recycled coarse aggregate replacement percentage, temperature and cooling method considered. The failure process of specimens was observed, and the mechanical properties such as bearing capacity, initial axial compression stiffness, ductility and energy dissipation capacity of the specimens were compared and analyzed. The results showed that the initial axial compression stiffness and energy dissipation capacity of RCFSST specimens were more affected by cooling method, while the bearing capacity and ductility of RCFCST specimens were more affected by cooling method. With the increase of temperature, the bearing capacity degradation, ductility change and energy consumption change of RCFSST specimens were more significant than that of RCFCST specimens. For the change of initial axial compression stiffness, when the temperature was lower, the degeneration of RCFSST specimens was greater, and when the temperature was higher, the degeneration of RCFCST specimens was greater. The change of the replacement percentage had a great influence on the bearing capacity of RCFSST specimens and initial axial compression stiffness of RCFCST.specimens With the increase of the replacement percentage, the ductility and energy dissipation coefficients of RCFSST specimens increased, while those of RCFCST specimens decreased.
In order to study the difference of axial compression properties of recycled concrete filled square(RCFSST) and circular steel tube (RCFCST) short column after being subjected to high temperatures and water cooling, 27 RCFSST and 27 RCFCST short columns were designed for axial compression test, with the variable parameters of recycled coarse aggregate replacement percentage, temperature and cooling method considered. The failure process of specimens was observed, and the mechanical properties such as bearing capacity, initial axial compression stiffness, ductility and energy dissipation capacity of the specimens were compared and analyzed. The results showed that the initial axial compression stiffness and energy dissipation capacity of RCFSST specimens were more affected by cooling method, while the bearing capacity and ductility of RCFCST specimens were more affected by cooling method. With the increase of temperature, the bearing capacity degradation, ductility change and energy consumption change of RCFSST specimens were more significant than that of RCFCST specimens. For the change of initial axial compression stiffness, when the temperature was lower, the degeneration of RCFSST specimens was greater, and when the temperature was higher, the degeneration of RCFCST specimens was greater. The change of the replacement percentage had a great influence on the bearing capacity of RCFSST specimens and initial axial compression stiffness of RCFCST.specimens With the increase of the replacement percentage, the ductility and energy dissipation coefficients of RCFSST specimens increased, while those of RCFCST specimens decreased.
2020, 50(2): 158-162,136.
doi: 10.13204/j.gyjz202002024
Abstract:
Comparing the similarities and differences of structural requirements, such as the deformation of the profiled steel sheet, the length of the overlap along the longitudinal direction, and the support length at the end of the plate, in the Chinese, American and European standards, the actual reasion and structural principles were analyzed, and the manufacturer's sheet metal requirements were compared. It could be concluded that the Chinese standard had more reasonable requirements on the support length of the profiled steel-concrete composite slab than the European standard. China should standardize the deflection limit of the profiled steel sheet and its deflection under different load types, and make a detailed division. At the same time, it was recommended to seal the longitudinal plate end lap joint part of the Chinese standard, thereby reducing the overlap length of the roof panel and saving steel.
Comparing the similarities and differences of structural requirements, such as the deformation of the profiled steel sheet, the length of the overlap along the longitudinal direction, and the support length at the end of the plate, in the Chinese, American and European standards, the actual reasion and structural principles were analyzed, and the manufacturer's sheet metal requirements were compared. It could be concluded that the Chinese standard had more reasonable requirements on the support length of the profiled steel-concrete composite slab than the European standard. China should standardize the deflection limit of the profiled steel sheet and its deflection under different load types, and make a detailed division. At the same time, it was recommended to seal the longitudinal plate end lap joint part of the Chinese standard, thereby reducing the overlap length of the roof panel and saving steel.
2020, 50(2): 163-168.
doi: 10.13204/j.gyjz202002025
Abstract:
Three groups of flexural members strengthened with different layers of carbon fiber sheet (CFS) were designed and manufactured, and their static flexural test were carried out, one group is fiber remforce popupner (FRP) reinforced concrete beam, one group is FRP reinforced engineereed cementitious composite (ECC) beam, and one group is FRP reinforced ECC-concrete composite beam. The effects of the number of layers of CFS on the ultimate load, failure mode, crack and deformation of strengthened ECC-concrete composite beams were studied. The results showed that under the same load, the deformation and crack width of the composite specimens and ECC specimens were smaller than those of the concrete specimens. ECC layered in the tension zone of the flexural members could effectively improve the capatity to resist deformation and cracks. The cracking load and ultimate load of the specimens strengthened by the CFS were higher than those of unstrengthened specimens. The ultimate load of the composite beam strengthened by one, two and three layers CFS were 12.5%, 16.6% and 19.7%, respectively, higher than that of unstrengthened beam. CFS could effectively improve the bearing capacity and capacity to resist deformation and cracks. The improvement effect increasesd with the increasing of number of CFS layers, but the increasing rate gradually decreased.
Three groups of flexural members strengthened with different layers of carbon fiber sheet (CFS) were designed and manufactured, and their static flexural test were carried out, one group is fiber remforce popupner (FRP) reinforced concrete beam, one group is FRP reinforced engineereed cementitious composite (ECC) beam, and one group is FRP reinforced ECC-concrete composite beam. The effects of the number of layers of CFS on the ultimate load, failure mode, crack and deformation of strengthened ECC-concrete composite beams were studied. The results showed that under the same load, the deformation and crack width of the composite specimens and ECC specimens were smaller than those of the concrete specimens. ECC layered in the tension zone of the flexural members could effectively improve the capatity to resist deformation and cracks. The cracking load and ultimate load of the specimens strengthened by the CFS were higher than those of unstrengthened specimens. The ultimate load of the composite beam strengthened by one, two and three layers CFS were 12.5%, 16.6% and 19.7%, respectively, higher than that of unstrengthened beam. CFS could effectively improve the bearing capacity and capacity to resist deformation and cracks. The improvement effect increasesd with the increasing of number of CFS layers, but the increasing rate gradually decreased.
2020, 50(2): 169-176,183.
doi: 10.13204/j.gyjz202002026
Abstract:
The prefabricated sandwich wall is a new type of wall, which integrates load-bearing, heat preservation and light weight. It consists of inner and outer leaf walls, connector and intermediate insulation board. The connector is a key component for connecting the inner and outer leaf walls and the thermal insulation boards. The current connector on the market are mostly imported from abroad, and the price is very high, it is not conducive to be widely used. Therefore, it is necessary to find a new type of connector with good mechanical properties, thermal insulation performance and low price. In the paper, glass fiber reinforced plastics profile was selected as the material of connector for the sandwich wall. Compared with the conventional connector, it showed the advantages of no cold and heat bridge, high strength, excellent corrosion resistance and low price. The pull-out and shear tests on the prefabricated sandwich wall with different types and sizes of fiberglass reinforced plastics were peformed, including rods, plates, L-section, H-section and C-section profiles. The thermal test of the sandwich wall was also carried out. The results showed that the glass fiber reinforced plastics had good shear and tensile strength as well as thermal insulation performance. The C-section connector had the largest crack-resisting load and ultimate load, which might be more suitable for the inner connector of prefabricated sandwich walls.
The prefabricated sandwich wall is a new type of wall, which integrates load-bearing, heat preservation and light weight. It consists of inner and outer leaf walls, connector and intermediate insulation board. The connector is a key component for connecting the inner and outer leaf walls and the thermal insulation boards. The current connector on the market are mostly imported from abroad, and the price is very high, it is not conducive to be widely used. Therefore, it is necessary to find a new type of connector with good mechanical properties, thermal insulation performance and low price. In the paper, glass fiber reinforced plastics profile was selected as the material of connector for the sandwich wall. Compared with the conventional connector, it showed the advantages of no cold and heat bridge, high strength, excellent corrosion resistance and low price. The pull-out and shear tests on the prefabricated sandwich wall with different types and sizes of fiberglass reinforced plastics were peformed, including rods, plates, L-section, H-section and C-section profiles. The thermal test of the sandwich wall was also carried out. The results showed that the glass fiber reinforced plastics had good shear and tensile strength as well as thermal insulation performance. The C-section connector had the largest crack-resisting load and ultimate load, which might be more suitable for the inner connector of prefabricated sandwich walls.
2020, 50(2): 177-183.
doi: 10.13204/j.gyjz202002027
Abstract:
In order to study the effects of size effect on the existing axial compressive performance of reinforced concrete columns strengthened with prestressed steel strips, a finite element analysis model was established based on the axial compressive test of steel strip reinforcement columns. The finite element analysis results were verified by experimental results. On this basis, the effects of different cross-section dimensions on the axial compression perfomance of steel strip reinforcement members were studied when the components were similar. The results showed that the increase in compressive strength and the increase in axial stiffness of similar members decreased with the increase of the cross-sectional dimensions of the members. The size effect coefficient was used to establish the calculation formula of the axial bearing capacity of the steel strip reinforcement column considering the size effect. The calculated values agreed well with the simulated values.
In order to study the effects of size effect on the existing axial compressive performance of reinforced concrete columns strengthened with prestressed steel strips, a finite element analysis model was established based on the axial compressive test of steel strip reinforcement columns. The finite element analysis results were verified by experimental results. On this basis, the effects of different cross-section dimensions on the axial compression perfomance of steel strip reinforcement members were studied when the components were similar. The results showed that the increase in compressive strength and the increase in axial stiffness of similar members decreased with the increase of the cross-sectional dimensions of the members. The size effect coefficient was used to establish the calculation formula of the axial bearing capacity of the steel strip reinforcement column considering the size effect. The calculated values agreed well with the simulated values.
2020, 50(2): 184-189.
doi: 10.13204/j.gyjz202002028
Abstract:
Taking the pedestal of Tongxin Mosque as the object, the geological radar (GPR) non-destructive detection method was used to prospect its structural diseases, the spatial-temporal distribution characteristics and disease mechanism of the soil in the pedestal were studied. The moisture field before and after the rain was compared and analyzed. According to the distribution characteristics, corresponding measures for reinforcement protection of the pedestal were proposed. The research results showed that the moisture was collected within the range of 0.8-2.2 m due to the poor compactness of the pedestal soil before the rain. After the rainwater infiltration, the soil moisture was obviously enhanced within the range of 0.5-2.4 m, the outer brick masonry and the arch migrated and infiltrated gradually, causing the cracking and weathering of outer brick masonry, as well as countertop sinking. The capatity against the rainwater erosion and the stability of the pedestal could be effectively enhanced by replacing the lime-soil pile, repairing the top waterproof system and the structural foundation.
Taking the pedestal of Tongxin Mosque as the object, the geological radar (GPR) non-destructive detection method was used to prospect its structural diseases, the spatial-temporal distribution characteristics and disease mechanism of the soil in the pedestal were studied. The moisture field before and after the rain was compared and analyzed. According to the distribution characteristics, corresponding measures for reinforcement protection of the pedestal were proposed. The research results showed that the moisture was collected within the range of 0.8-2.2 m due to the poor compactness of the pedestal soil before the rain. After the rainwater infiltration, the soil moisture was obviously enhanced within the range of 0.5-2.4 m, the outer brick masonry and the arch migrated and infiltrated gradually, causing the cracking and weathering of outer brick masonry, as well as countertop sinking. The capatity against the rainwater erosion and the stability of the pedestal could be effectively enhanced by replacing the lime-soil pile, repairing the top waterproof system and the structural foundation.
2020, 50(2): 190-197.
doi: 10.13204/j.gyjz202002029
Abstract:
Under long-term loading, the ancient buildings in the Forbidden City have inevitable structural problems due to their construction characteristics and material defects. Correspondingly, the craftsmen had accumulated abundant strengthening techniques during engineering practice. Some examples were taken for amalysis in the paper, such as column bottom strengthening and face beam supporting of the Hall of Supreme Harmony, purlin and tie beam wrapping of the Hall of Central Harmony, tenon-mortise joint connected by additional iron component of an ancient building in Jiange county of Sichuan and so on. The strengthening mechanism and effects were discussed. The results showed that the strengthening techniques for the ancient buildings in the Forbidden City could effectively solve the structural problems of the building components and increase the service life of the buildings.
Under long-term loading, the ancient buildings in the Forbidden City have inevitable structural problems due to their construction characteristics and material defects. Correspondingly, the craftsmen had accumulated abundant strengthening techniques during engineering practice. Some examples were taken for amalysis in the paper, such as column bottom strengthening and face beam supporting of the Hall of Supreme Harmony, purlin and tie beam wrapping of the Hall of Central Harmony, tenon-mortise joint connected by additional iron component of an ancient building in Jiange county of Sichuan and so on. The strengthening mechanism and effects were discussed. The results showed that the strengthening techniques for the ancient buildings in the Forbidden City could effectively solve the structural problems of the building components and increase the service life of the buildings.
2020, 50(2): 198-202,189.
doi: 10.13204/j.gyjz202002030
Abstract:
As a banner of the modernist architectural liberation movement, the seven principles of Modern Architectural Language have had a profound impact on the architectural design of the time. By interpreting the modern expression of the traditional architectural language of Chinese contemporary architect Wang Shu, this thesis re-examines the positive significance of the seven principles of modern architecture for the contemporary architectural design. At the same time, through in-depth analysis of the differences between Wang Shu's architectural language and the seven principles "respect history, Inheriting traditional skills and following the concept of sustainable development", it points out that the "single-start, mechanical production, and non-consumption" advocated by the seven principles of modern architecture is no longer applicable in different national conditions and different cultural backgrounds;Language needs to adhere to the tradition, highlight individuality, and take the road of sustainable development. Only by grasping the relationship between contemporary architecture system and traditional architectural culture can Chinese contemporary architects have the dual vision of "modern" and "contemporary" and maintain dynamic and open Creative thinking, moving forward and building the future together.
As a banner of the modernist architectural liberation movement, the seven principles of Modern Architectural Language have had a profound impact on the architectural design of the time. By interpreting the modern expression of the traditional architectural language of Chinese contemporary architect Wang Shu, this thesis re-examines the positive significance of the seven principles of modern architecture for the contemporary architectural design. At the same time, through in-depth analysis of the differences between Wang Shu's architectural language and the seven principles "respect history, Inheriting traditional skills and following the concept of sustainable development", it points out that the "single-start, mechanical production, and non-consumption" advocated by the seven principles of modern architecture is no longer applicable in different national conditions and different cultural backgrounds;Language needs to adhere to the tradition, highlight individuality, and take the road of sustainable development. Only by grasping the relationship between contemporary architecture system and traditional architectural culture can Chinese contemporary architects have the dual vision of "modern" and "contemporary" and maintain dynamic and open Creative thinking, moving forward and building the future together.
