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2015 Vol. 45, No. 6
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2015, 45(6): 1-6.
doi: 10.13204/j.gyjz201506001
Abstract:
The pull-out test was conducted on 30 specimens of fiber reinforced polymer ( FRP) rebars embedded into concrete blocks． The effects of FRP types，diameters of FRP rebars，bond length and concrete strength on bond behavior were investigated． Based on the test results，the bond-slip constitutive model and bond strength of FRP rebar-to-concrete interface were established，whose results were compared with test results． The test results showed that the failure mode was fracture or sliding out of FRP rebars． The most important factor on interfacial bond strength was type of FRP rebar． The calculated results indicated that the proposed model had a good agreement with the test data，which could effectively predict the interfacial bond strength and the relationship of bond shear stress and interfacial slip．
The pull-out test was conducted on 30 specimens of fiber reinforced polymer ( FRP) rebars embedded into concrete blocks． The effects of FRP types，diameters of FRP rebars，bond length and concrete strength on bond behavior were investigated． Based on the test results，the bond-slip constitutive model and bond strength of FRP rebar-to-concrete interface were established，whose results were compared with test results． The test results showed that the failure mode was fracture or sliding out of FRP rebars． The most important factor on interfacial bond strength was type of FRP rebar． The calculated results indicated that the proposed model had a good agreement with the test data，which could effectively predict the interfacial bond strength and the relationship of bond shear stress and interfacial slip．
2015, 45(6): 7-11.
doi: 10.13204/j.gyjz201506002
Abstract:
Five CFRP-PCPs composite reinforced concrete continuous beams under crack test were studied． On the basis of the tests，calculation formulas for average crack distance and maximum crack width of each controlled section CFRP-PCPs composite reinforced concrete continuous beams were presented． The test results verified the feasibility of the calculation formulas，which provided a theoretical support for the application of CFRP-PCPs in practical projects． The experimental results show that the crack development of CFRP-PCPs composite reinforced concrete continuous beams is related to the tension control stress and the cross-sectional area of the composite bar．
Five CFRP-PCPs composite reinforced concrete continuous beams under crack test were studied． On the basis of the tests，calculation formulas for average crack distance and maximum crack width of each controlled section CFRP-PCPs composite reinforced concrete continuous beams were presented． The test results verified the feasibility of the calculation formulas，which provided a theoretical support for the application of CFRP-PCPs in practical projects． The experimental results show that the crack development of CFRP-PCPs composite reinforced concrete continuous beams is related to the tension control stress and the cross-sectional area of the composite bar．
2015, 45(6): 12-15.
doi: 10.13204/j.gyjz201506003
Abstract:
The compressive strength of AFRP-wrapped concrete column under high strain rate was experimentally studied utilizing an 100 mm diameter SHPB apparatus． The results indicate that the compressive strength was enhanced under high strain rate and presented clear strain rate dependence; when the strain rate was kept similar，the dynamic compressive strength first increased and then decreased，in which 2-ply AFRP-wrapped concrete exhibited the best enhancement property． Besides，a new ultimate strength model was obtained by modifying the Bethet strength model considering strain rate effect．
The compressive strength of AFRP-wrapped concrete column under high strain rate was experimentally studied utilizing an 100 mm diameter SHPB apparatus． The results indicate that the compressive strength was enhanced under high strain rate and presented clear strain rate dependence; when the strain rate was kept similar，the dynamic compressive strength first increased and then decreased，in which 2-ply AFRP-wrapped concrete exhibited the best enhancement property． Besides，a new ultimate strength model was obtained by modifying the Bethet strength model considering strain rate effect．
2015, 45(6): 16-21.
doi: 10.13204/j.gyjz201506004
Abstract:
FRP composite material has good insulation and stain resistance，which can greatly improve the safety level of transmission line and reduce maintenance cost． Based on the background of 380 kV transmission line reconstruction，in the project，two kinds of specifications of FRP composite steel casing 200 10 and 272 12 were used，and their tensile properties were studied，the test was divided into the design load test ( engineering application) and ultimate bearing capacity test ( failure mode) ; the load-displacement curves，strain disciplinarian law and failure mode etc were got． It was found that the bearing capacity of steel casing of bonded joints was mainly decided by the adhesive strength，the failure mode is brittleness form． Finally，in view of the tensile design of the FRP composite bushing，some design suggestions were proposed．
FRP composite material has good insulation and stain resistance，which can greatly improve the safety level of transmission line and reduce maintenance cost． Based on the background of 380 kV transmission line reconstruction，in the project，two kinds of specifications of FRP composite steel casing 200 10 and 272 12 were used，and their tensile properties were studied，the test was divided into the design load test ( engineering application) and ultimate bearing capacity test ( failure mode) ; the load-displacement curves，strain disciplinarian law and failure mode etc were got． It was found that the bearing capacity of steel casing of bonded joints was mainly decided by the adhesive strength，the failure mode is brittleness form． Finally，in view of the tensile design of the FRP composite bushing，some design suggestions were proposed．
2015, 45(6): 22-26.
doi: 10.13204/j.gyjz201506005
Abstract:
Study of prestress loss is one of the key technologing in prestressed FRP reinforcement． This paper presented a new type of stretching and anchoring integral anchorage for prestressed FRP reinforced damage internal pressure steel pipe，analysed the generation mechanism of friction loss，anchorage loss，relaxation loss caused by the strengthening process． By elastic-plastic mechanical plane stress solution and friction loss test research，the stress distribution model of fiber sheet after the friction loss was established． Based on the analysis of relaxation loss test and anchorage loss test，it was found that the anchorage loss existed in the first 80 minutes of the process and that the anchorage loss was related to the locking degree of bolt． Besides the relaxation loss percentage and the change law of relaxation loss with the time were also got．
Study of prestress loss is one of the key technologing in prestressed FRP reinforcement． This paper presented a new type of stretching and anchoring integral anchorage for prestressed FRP reinforced damage internal pressure steel pipe，analysed the generation mechanism of friction loss，anchorage loss，relaxation loss caused by the strengthening process． By elastic-plastic mechanical plane stress solution and friction loss test research，the stress distribution model of fiber sheet after the friction loss was established． Based on the analysis of relaxation loss test and anchorage loss test，it was found that the anchorage loss existed in the first 80 minutes of the process and that the anchorage loss was related to the locking degree of bolt． Besides the relaxation loss percentage and the change law of relaxation loss with the time were also got．
2015, 45(6): 27-30.
doi: 10.13204/j.gyjz201506006
Abstract:
When carbon fiber reinforced polymer ( CFRP) was used in the actual steel structure reinforcement projects，structural failure often occurs due to the cyclic temperature and humid environment． This paper presented an experimental study on the tension capacity of 8 steel-CFRP strap joints including 2 specimens after 90 wet-dry cycles and 2 specimens after 180 wet-dry cycles． The ultimate bearing capacity，the failure characteristics of the steel and CFRP interface were studied after dry-wet cycles． The test results showed that steel-CFRP strap joints tensile bearing capacity decreased significantly under the influence of wet and dry cycles． Bearing capacity of the specimens stabilized after 90 times of wet-dry cycles． And through theoretical formula it was deduced results of maximum principal interface stress，which were compared with the test results and a deviation between the two was within 15%． Which verified the accuracy of theoretical formula．
When carbon fiber reinforced polymer ( CFRP) was used in the actual steel structure reinforcement projects，structural failure often occurs due to the cyclic temperature and humid environment． This paper presented an experimental study on the tension capacity of 8 steel-CFRP strap joints including 2 specimens after 90 wet-dry cycles and 2 specimens after 180 wet-dry cycles． The ultimate bearing capacity，the failure characteristics of the steel and CFRP interface were studied after dry-wet cycles． The test results showed that steel-CFRP strap joints tensile bearing capacity decreased significantly under the influence of wet and dry cycles． Bearing capacity of the specimens stabilized after 90 times of wet-dry cycles． And through theoretical formula it was deduced results of maximum principal interface stress，which were compared with the test results and a deviation between the two was within 15%． Which verified the accuracy of theoretical formula．
2015, 45(6): 31-36.
doi: 10.13204/j.gyjz201506007
Abstract:
FRP composites which possess advantages including light-weight，anti-corrosion and good insulating property，have broad application prospects in electric power industry． Based on the static tension and compression research，it was carried out full-scale fatigue tests for adhesive-bolt-hybrid connections． The fatigue life and the failure mode of this kind of connection were analyzed in the different stress amplitude and loading conditions． The whole process of development of cracks at the adhesive joint was revealed under constant amplitude cyclic loading and the degradation index of structure bearing capacity was also given． The results showed that the end of connection using epoxy resin adhesives as bonding materials between the complex bar and the steel sleeve was pulled out，which was a typical brittle failure． The shear bearing capacity of the joint was low，which had greater discrepancies with theoretical calculation values． The bearing capacity only decreased by 6. 8% after 2 million cycles under the tensioncompression conditions， indicated that the adhesive joints had excellent shock absorption and anti-fatigue performance． Which provided a basis for engineering applications and theoretical analysis of complex tower structure．
FRP composites which possess advantages including light-weight，anti-corrosion and good insulating property，have broad application prospects in electric power industry． Based on the static tension and compression research，it was carried out full-scale fatigue tests for adhesive-bolt-hybrid connections． The fatigue life and the failure mode of this kind of connection were analyzed in the different stress amplitude and loading conditions． The whole process of development of cracks at the adhesive joint was revealed under constant amplitude cyclic loading and the degradation index of structure bearing capacity was also given． The results showed that the end of connection using epoxy resin adhesives as bonding materials between the complex bar and the steel sleeve was pulled out，which was a typical brittle failure． The shear bearing capacity of the joint was low，which had greater discrepancies with theoretical calculation values． The bearing capacity only decreased by 6. 8% after 2 million cycles under the tensioncompression conditions， indicated that the adhesive joints had excellent shock absorption and anti-fatigue performance． Which provided a basis for engineering applications and theoretical analysis of complex tower structure．
2015, 45(6): 37-42.
doi: 10.13204/j.gyjz201506008
Abstract:
Through the bending test of the composite components for a glass fiber fabric reinforced concrete formwork components， the paper discussed the influence on the overall bending strength of overlapped beams of different treatments of the TRC formwork，different after pouring concrete intensity and different layer number of textile． The result showed that TRC panel did not need special treatment and it could work together with after pouring concrete very well． For the same kind of TRC formwork， the lower concrete strength， the more obvious enhancement effect on its bending strength． Textile has areinforcedconstraint function， its participation is benificial to the improvement of the component bending strength and the number of the fibres is not the more the better，but it needs the optimal number of fibres．
Through the bending test of the composite components for a glass fiber fabric reinforced concrete formwork components， the paper discussed the influence on the overall bending strength of overlapped beams of different treatments of the TRC formwork，different after pouring concrete intensity and different layer number of textile． The result showed that TRC panel did not need special treatment and it could work together with after pouring concrete very well． For the same kind of TRC formwork， the lower concrete strength， the more obvious enhancement effect on its bending strength． Textile has areinforcedconstraint function， its participation is benificial to the improvement of the component bending strength and the number of the fibres is not the more the better，but it needs the optimal number of fibres．
2015, 45(6): 43-46.
doi: 10.13204/j.gyjz201506009
Abstract:
Selecting 8 Xinjiang poplar beams reinforced basalt fiber cloth ( BFRP) U-type hoop and study flexural properties according to the changes of the U-shaped hoop number and location of the comparative， analyze the damage phenomena，neutral axis position changes， the bearing capacity，deflection and other performance indicators． The results showed that the BFRP sheet on the beam bottom peeled off when U hoop was not pasted on the beam，pasting U-hoop had a certain anchor role， the changes in number and location of the U-shaped hoop had different effect on the beam flexural bearing capacity and deflection，and consistent move of the neutral axis position had a tendency to move towards the compression zone．
Selecting 8 Xinjiang poplar beams reinforced basalt fiber cloth ( BFRP) U-type hoop and study flexural properties according to the changes of the U-shaped hoop number and location of the comparative， analyze the damage phenomena，neutral axis position changes， the bearing capacity，deflection and other performance indicators． The results showed that the BFRP sheet on the beam bottom peeled off when U hoop was not pasted on the beam，pasting U-hoop had a certain anchor role， the changes in number and location of the U-shaped hoop had different effect on the beam flexural bearing capacity and deflection，and consistent move of the neutral axis position had a tendency to move towards the compression zone．
2015, 45(6): 47-50.
doi: 10.13204/j.gyjz201506010
Abstract:
The renovaion of shanty towns is not only a significant livelihood project，but also a major development project． Renovation of shanty towns in historical and cultural blocks is even a cultural renaissance project as well as an industrial development project． It was analyzed the difficulties in renovation of this kind of typical shanty towns， tried to introduce a Logit mathematical model tool; starting from the transportation accessibility，it was built a Logit dynamic data model based on human flow statistics． Through migration simulation assessment，and it was then conducted ranking research on renovation projects in the shanty towns，so as to realize the all-round improvement of human settlement environment construction based on the integration of people's livelihood，culture and industry．
The renovaion of shanty towns is not only a significant livelihood project，but also a major development project． Renovation of shanty towns in historical and cultural blocks is even a cultural renaissance project as well as an industrial development project． It was analyzed the difficulties in renovation of this kind of typical shanty towns， tried to introduce a Logit mathematical model tool; starting from the transportation accessibility，it was built a Logit dynamic data model based on human flow statistics． Through migration simulation assessment，and it was then conducted ranking research on renovation projects in the shanty towns，so as to realize the all-round improvement of human settlement environment construction based on the integration of people's livelihood，culture and industry．
2015, 45(6): 51-54.
doi: 10.13204/j.gyjz201506011
Abstract:
This paper expounded the basic strategy of green ecological design by taking the solar house buildingALL GREENin International Solar Decathlon competition for example． In the passive ecological strategy，the paper Analysed the methods and specialities of natural lighting，natural ventilation，as well as building structural system; in the active ecological strategy，the paper introduced the methods and specialities of solar photovoltaic roof integration， solar hot water system， reclaimed water system and intelligent residential system． The industrialization and marketization ofALL GREENwere analyzed，finally it was summarized the defects in the design and enlightenment from it，it was expected to have some reference to the design of similar solar residential houses with zero energy．
This paper expounded the basic strategy of green ecological design by taking the solar house buildingALL GREENin International Solar Decathlon competition for example． In the passive ecological strategy，the paper Analysed the methods and specialities of natural lighting，natural ventilation，as well as building structural system; in the active ecological strategy，the paper introduced the methods and specialities of solar photovoltaic roof integration， solar hot water system， reclaimed water system and intelligent residential system． The industrialization and marketization ofALL GREENwere analyzed，finally it was summarized the defects in the design and enlightenment from it，it was expected to have some reference to the design of similar solar residential houses with zero energy．
2015, 45(6): 55-59.
doi: 10.13204/j.gyjz201506012
Abstract:
Manchukuo Standardized Residential Design Atlas is the source book for the design and construction of small and medium sizedJapanese-style houseswhich is the important historical document reflecting the former construction level of standardized low and multi-layer housings in Manchuyao Period． Based on the study of Manchukuo Standardized Residential Design Atlas，it was made a comprehensive field survey to Changchun existing standardizedJapanese-style housesin Japanese occupation period． It was recognized that the advanced techniques， methods and materials at that time were used for such Japanese-style houses，which provided an important reference for design and construction of modern buildings in northeastern area of China．
Manchukuo Standardized Residential Design Atlas is the source book for the design and construction of small and medium sizedJapanese-style houseswhich is the important historical document reflecting the former construction level of standardized low and multi-layer housings in Manchuyao Period． Based on the study of Manchukuo Standardized Residential Design Atlas，it was made a comprehensive field survey to Changchun existing standardizedJapanese-style housesin Japanese occupation period． It was recognized that the advanced techniques， methods and materials at that time were used for such Japanese-style houses，which provided an important reference for design and construction of modern buildings in northeastern area of China．
2015, 45(6): 60-65.
doi: 10.13204/j.gyjz201506013
Abstract:
This paper is focusing on the difference between the circumstances of the particle dampers application in mechanical，astronautics and civil engineering seismic controls． A theoretical analysis was conducted aiming at the seismic control of the particle dampers with low frequency and amplitude． The analysis indicated that the accumulation was one of the key factors to the application of the particle dampers in civil engineering． Thus the starting conditions for the particle oscillation under different accumulating states were derived． Based on the Hertz contact theory and the Coulomb law of friction，a particle-SDOF oscillating system was established with MATLAB， and the starting conditions for the particle oscillation and the damping performance were also analyzed．
This paper is focusing on the difference between the circumstances of the particle dampers application in mechanical，astronautics and civil engineering seismic controls． A theoretical analysis was conducted aiming at the seismic control of the particle dampers with low frequency and amplitude． The analysis indicated that the accumulation was one of the key factors to the application of the particle dampers in civil engineering． Thus the starting conditions for the particle oscillation under different accumulating states were derived． Based on the Hertz contact theory and the Coulomb law of friction，a particle-SDOF oscillating system was established with MATLAB， and the starting conditions for the particle oscillation and the damping performance were also analyzed．
2015, 45(6): 66-71.
doi: 10.13204/j.gyjz201506014
Abstract:
Based on a large number of test results at home and abroad，through theoretical analysis and experimental research，the relationship among the limiting displacement drift，the ductility of HSC columns and axial compression ratio，confining reinforcement characteristic values，the cover area as well as longitudinal reinforcement ratio was set up; the design formula for calculating the confining reinforcement and the minimum confining reinforcement characteristic values of HSC columns at different seismic levels were proposed． By way of comparison，it was indicated that the amount of stirrup ratio calculated by proposed design method was higher than current standards and ACI 318 － 05 standards，but lower than CSA A23. 3 － 04 and NZS 3101 standards．
Based on a large number of test results at home and abroad，through theoretical analysis and experimental research，the relationship among the limiting displacement drift，the ductility of HSC columns and axial compression ratio，confining reinforcement characteristic values，the cover area as well as longitudinal reinforcement ratio was set up; the design formula for calculating the confining reinforcement and the minimum confining reinforcement characteristic values of HSC columns at different seismic levels were proposed． By way of comparison，it was indicated that the amount of stirrup ratio calculated by proposed design method was higher than current standards and ACI 318 － 05 standards，but lower than CSA A23. 3 － 04 and NZS 3101 standards．
2015, 45(6): 72-76.
doi: 10.13204/j.gyjz201506015
Abstract:
The analysis of seismic energy responses of multi-ribbed composite slab structures ( MRSS ) was an important subject in the research and application field of MRSS． The distribution proportions of hysteretic energy related to component was a keypoint to realize the analysis of seismic energy responses． Based on the developed nonlinear numerical analysis model of MRSS，elasto-plastic time-history analyses were carried out on 150 examples， each of 15 MRSS under 10 seismic waves with large-earthquake level，which were designed according to current related codes and specifications． A series of formulas for distribution proportions of hysteretic energy related to component of MRSS were proposed and established． The comparative studies showed that the proposed formulas could be used in MRSS whose total number of storeies was less than 15．
The analysis of seismic energy responses of multi-ribbed composite slab structures ( MRSS ) was an important subject in the research and application field of MRSS． The distribution proportions of hysteretic energy related to component was a keypoint to realize the analysis of seismic energy responses． Based on the developed nonlinear numerical analysis model of MRSS，elasto-plastic time-history analyses were carried out on 150 examples， each of 15 MRSS under 10 seismic waves with large-earthquake level，which were designed according to current related codes and specifications． A series of formulas for distribution proportions of hysteretic energy related to component of MRSS were proposed and established． The comparative studies showed that the proposed formulas could be used in MRSS whose total number of storeies was less than 15．
2015, 45(6): 77-81.
doi: 10.13204/j.gyjz201506016
Abstract:
For the energy analysis problem of large and complex structures，SAP 2000 was used to established a model of the enlarged-base twin-tower with connective structures，and elastic energy analysis was carried out by using the corresponding program of MATLAB and SAP 2000，and gave the relationship between the structural energy response and the energy response of a single degree of freedom system was given in order to carry out a structural vibration modal decomposition energy analysis and build an energy response spectrum． It was studied the elasticplastic energy response of the structure under the action of three-dimensional seism，whose result was compared with that of the case without connected structures． The studies showed that the vibration modal decomposition energy analysis method could quickly，efficiently estimate the energy response of structures，and the aseismic performance of a connecting structure was better than non-connected structure in a certain extent．
For the energy analysis problem of large and complex structures，SAP 2000 was used to established a model of the enlarged-base twin-tower with connective structures，and elastic energy analysis was carried out by using the corresponding program of MATLAB and SAP 2000，and gave the relationship between the structural energy response and the energy response of a single degree of freedom system was given in order to carry out a structural vibration modal decomposition energy analysis and build an energy response spectrum． It was studied the elasticplastic energy response of the structure under the action of three-dimensional seism，whose result was compared with that of the case without connected structures． The studies showed that the vibration modal decomposition energy analysis method could quickly，efficiently estimate the energy response of structures，and the aseismic performance of a connecting structure was better than non-connected structure in a certain extent．
2015, 45(6): 82-86.
doi: 10.13204/j.gyjz201506017
Abstract:
Viscous damping wall is an innovative high efficient energy dissipation device for reducing the dynamic responses of building structures． It has a preferable effect of suppressing the vibration amplitude of the building structures under both earthquake and wind． The element design of the structure can be optimized since the internal force of structure member has been reduced by additional damping ratio provided by the viscous damping wall． A new method of integrated optimal design of tall building structures with viscous damping walls was put forward． Both the anti-seismic performance objective and size control condition of members for the tall building structure were explored， the appropriate arrangement of the viscous damping wall could make the structure comply with the design requirement． The optimal position of the viscous damping wall based on integrated optimal design was applied on a 300 m super tall building of central core tube and braced frame，the result revealed: the integrated optimal design of tall building structures with viscous damping walls have economical benefit for the structure．
Viscous damping wall is an innovative high efficient energy dissipation device for reducing the dynamic responses of building structures． It has a preferable effect of suppressing the vibration amplitude of the building structures under both earthquake and wind． The element design of the structure can be optimized since the internal force of structure member has been reduced by additional damping ratio provided by the viscous damping wall． A new method of integrated optimal design of tall building structures with viscous damping walls was put forward． Both the anti-seismic performance objective and size control condition of members for the tall building structure were explored， the appropriate arrangement of the viscous damping wall could make the structure comply with the design requirement． The optimal position of the viscous damping wall based on integrated optimal design was applied on a 300 m super tall building of central core tube and braced frame，the result revealed: the integrated optimal design of tall building structures with viscous damping walls have economical benefit for the structure．
2015, 45(6): 87-92.
doi: 10.13204/j.gyjz201506018
Abstract:
The stress of a soil particle at a point in the soil-structure interface layer not only depends on the strain and deformation history of the point，but also depends on the stresses of other points near the point． According to the early non-local theory，considering the influence and interaction between the tiny structures of the non-homogeneous materials，the non-local plastic shear strain was expressed as the weighted average of the corresponding parameters of itself，and also considering the effect of rough ness of structural surface on the mechanical characteristics of the soil in the interface layer，the constitutive model of soil-structure interface based on strain gradient plasticity theory was established under relatively low normal stress condition． Each parameter in the model had a clear physical meaning． The results showed that the model could be used to study the relationship between shear stress and shear strain， especially in the case that the characteristics of strain softening after the peak shear stress．
The stress of a soil particle at a point in the soil-structure interface layer not only depends on the strain and deformation history of the point，but also depends on the stresses of other points near the point． According to the early non-local theory，considering the influence and interaction between the tiny structures of the non-homogeneous materials，the non-local plastic shear strain was expressed as the weighted average of the corresponding parameters of itself，and also considering the effect of rough ness of structural surface on the mechanical characteristics of the soil in the interface layer，the constitutive model of soil-structure interface based on strain gradient plasticity theory was established under relatively low normal stress condition． Each parameter in the model had a clear physical meaning． The results showed that the model could be used to study the relationship between shear stress and shear strain， especially in the case that the characteristics of strain softening after the peak shear stress．
2015, 45(6): 93-97.
doi: 10.13204/j.gyjz201506019
Abstract:
On the basis of the construction on a high-filled collapsible loess foundation of a airport in the northwest of Shanxi，according to the initial design and the initial stability analysis results of the slope，the numerical stability analysis of 10 typical cross sections of the high-filled slope of the airport was performed by combined with a large-scale centrifugal model test． The research results showed that the slope of the airport was stable at natural moisture content， while unstable at full saturation． Deformations on the surface of the filling body were mainly vertical ones with horizontal displacements towards the outside of the slope． Also，the vertical deformation was bigger when it closer to the surface of the slope． The maximum shear strain of the slope was mainly concentrated on the contact surface between the filling body and the natural subsoil． Moreover，when the slope was broken，the displacements of the top and the bottom of the slope generally increased with the increase of the height and the thickness of the slope．
On the basis of the construction on a high-filled collapsible loess foundation of a airport in the northwest of Shanxi，according to the initial design and the initial stability analysis results of the slope，the numerical stability analysis of 10 typical cross sections of the high-filled slope of the airport was performed by combined with a large-scale centrifugal model test． The research results showed that the slope of the airport was stable at natural moisture content， while unstable at full saturation． Deformations on the surface of the filling body were mainly vertical ones with horizontal displacements towards the outside of the slope． Also，the vertical deformation was bigger when it closer to the surface of the slope． The maximum shear strain of the slope was mainly concentrated on the contact surface between the filling body and the natural subsoil． Moreover，when the slope was broken，the displacements of the top and the bottom of the slope generally increased with the increase of the height and the thickness of the slope．
2015, 45(6): 98-102.
doi: 10.13204/j.gyjz201506020
Abstract:
As for piles under negative skin friction，there exists a sequence loaded on pile head and surcharge around piles． However，the influence of the loaded sequence on negative skin friction is less studied． Aiming at researching the influence of the loaded sequence，the indoor model tests for negative skin friction on single pile in sand were carried out． The axial force of pile shaft，settlement of pile top and each soil layer were measured． The results showed that the influences of the loaded sequence were obvious on the negative skin friction of the pile in sand． When the surcharge around piles were loaded first，the neutral plane were closer to piles tips． Settlement of piles loaded on surcharge around piles first were significantly smaller than that of piles loaded on the tops first． The pile head settlements under the action of surcharge load were basically identical with the different loaded sequence，and the increase amplitudes of pile head settlements slowed down gradually with the increasing of surcharge load around piles．
As for piles under negative skin friction，there exists a sequence loaded on pile head and surcharge around piles． However，the influence of the loaded sequence on negative skin friction is less studied． Aiming at researching the influence of the loaded sequence，the indoor model tests for negative skin friction on single pile in sand were carried out． The axial force of pile shaft，settlement of pile top and each soil layer were measured． The results showed that the influences of the loaded sequence were obvious on the negative skin friction of the pile in sand． When the surcharge around piles were loaded first，the neutral plane were closer to piles tips． Settlement of piles loaded on surcharge around piles first were significantly smaller than that of piles loaded on the tops first． The pile head settlements under the action of surcharge load were basically identical with the different loaded sequence，and the increase amplitudes of pile head settlements slowed down gradually with the increasing of surcharge load around piles．
2015, 45(6): 103-109.
doi: 10.13204/j.gyjz201506021
Abstract:
Aiming at the state of lower pullout bearing capacity for normal prestressed anchor，three typical kinds of anchorload-dispersive anchor，post high pressure grouting and under-reamed ground anchor，were discussed by adopting theoretical analysis，field test and investigation． The bearing mechanism，the technical connotation，work characteristic，implementation essentials and application conditions of the three ones were discussed，the anchorage effects were also reflected by several measurements in situ．
Aiming at the state of lower pullout bearing capacity for normal prestressed anchor，three typical kinds of anchorload-dispersive anchor，post high pressure grouting and under-reamed ground anchor，were discussed by adopting theoretical analysis，field test and investigation． The bearing mechanism，the technical connotation，work characteristic，implementation essentials and application conditions of the three ones were discussed，the anchorage effects were also reflected by several measurements in situ．
2015, 45(6): 110-117.
doi: 10.13204/j.gyjz201506022
Abstract:
The elastic-unloading mechanical calculating model between the existing structure and the new one was established，the solution to additional stress among the whole semi-infinite body was discussed based on the Mindlin solution，and then the analytical formula for additional stress coefficient is derived by using the superposition principles， odd function properties and symmetry of load． The analytic expressions for the unloading vertical stress at any point in the interior of semi-infinite body subject to single and double rectangular uniform load were obtained． The study result can be applied to calculate the unloading-additional stress and the rising deformation of the existing structure induced by construction of the newly-built subway station and the excavations over it．
The elastic-unloading mechanical calculating model between the existing structure and the new one was established，the solution to additional stress among the whole semi-infinite body was discussed based on the Mindlin solution，and then the analytical formula for additional stress coefficient is derived by using the superposition principles， odd function properties and symmetry of load． The analytic expressions for the unloading vertical stress at any point in the interior of semi-infinite body subject to single and double rectangular uniform load were obtained． The study result can be applied to calculate the unloading-additional stress and the rising deformation of the existing structure induced by construction of the newly-built subway station and the excavations over it．
2015, 45(6): 118-122.
doi: 10.13204/j.gyjz201506023
Abstract:
Full size experiments were used to analyses the bearing capacity of a new-type horizontal formwork of fast installation and early dismantling，the tests focused on testing the performance influence of construction loads on the system and the mechanical properties of the system and engineering practicality after early demolition． It was concluded that the frame body was safe under 18. 5 kN load by setting six strain-points and eight displacement-points to measure on the experimental model under continuous load and also measuring the overall deformation and bearing capacity of the frame body． In addition，when the new pouring concrete strength reaches 38%，the frame body was removed first the early and retaining pole support retained independently． The experiment results showed that the structure was in a safe state． The experiment results provide strong support for the promotion and application of the frameworks，and the experiment methods also provide some reference for the experiments of relevant scaffold．
Full size experiments were used to analyses the bearing capacity of a new-type horizontal formwork of fast installation and early dismantling，the tests focused on testing the performance influence of construction loads on the system and the mechanical properties of the system and engineering practicality after early demolition． It was concluded that the frame body was safe under 18. 5 kN load by setting six strain-points and eight displacement-points to measure on the experimental model under continuous load and also measuring the overall deformation and bearing capacity of the frame body． In addition，when the new pouring concrete strength reaches 38%，the frame body was removed first the early and retaining pole support retained independently． The experiment results showed that the structure was in a safe state． The experiment results provide strong support for the promotion and application of the frameworks，and the experiment methods also provide some reference for the experiments of relevant scaffold．
2015, 45(6): 123-127.
doi: 10.13204/j.gyjz201506024
Abstract:
In order to study the construction of mega frame-cable bracing structures，eight construction schemes were designed． Comparative study was made on the structural deformation and inner force of each scheme，as well as that under disposable loading scheme． Results show that the structural force and deformation differ from each other under different construction schemes and show relatively smaller values under some construction schemes，which can provide some guidance for the construction of mega frame-cable bracing structures．
In order to study the construction of mega frame-cable bracing structures，eight construction schemes were designed． Comparative study was made on the structural deformation and inner force of each scheme，as well as that under disposable loading scheme． Results show that the structural force and deformation differ from each other under different construction schemes and show relatively smaller values under some construction schemes，which can provide some guidance for the construction of mega frame-cable bracing structures．
2015, 45(6): 128-132.
doi: 10.13204/j.gyjz201506025
Abstract:
A prilling tower features complicated structures，whose construction is very difficult． A super massive sliding form was used for the construction of the prilling tower for Vlan Fertilizer Plant． Hence still higher requirements were proposed for the construction technology，construction quality and inspection precision control． Through the exploration of practice of this project，it was realized the integration of construction elements to ensure the quality and safety of the constructions，thus finishing the project on time．
A prilling tower features complicated structures，whose construction is very difficult． A super massive sliding form was used for the construction of the prilling tower for Vlan Fertilizer Plant． Hence still higher requirements were proposed for the construction technology，construction quality and inspection precision control． Through the exploration of practice of this project，it was realized the integration of construction elements to ensure the quality and safety of the constructions，thus finishing the project on time．
2015, 45(6): 133-136.
doi: 10.13204/j.gyjz201506026
Abstract:
In order to study the distribution characteristics of wind load of suspended latticed shell structure under typhoon，the Fluent software and computational fluid dynamics( CFD) technology was applied in this research． the numerical simulation of distribution law of wind load on shell structure under different working conditions of typhoon was carried out based on SST k － turbulence model and Tianpus turbulent intensity in this paper． And the distribution law of wind load under different wind directions and elevations was analyzed． The comparison of numerical simulation result and shape coefficient according to Load Code for Design of Building Structures ( GB 500092012) shows that the average wind pressure coefficient in numerical simulation was larger than the value of wind load shape coefficient in the load code． The result has certain reference for typhoon-resistant design of large-span spatial structure for references．
In order to study the distribution characteristics of wind load of suspended latticed shell structure under typhoon，the Fluent software and computational fluid dynamics( CFD) technology was applied in this research． the numerical simulation of distribution law of wind load on shell structure under different working conditions of typhoon was carried out based on SST k － turbulence model and Tianpus turbulent intensity in this paper． And the distribution law of wind load under different wind directions and elevations was analyzed． The comparison of numerical simulation result and shape coefficient according to Load Code for Design of Building Structures ( GB 500092012) shows that the average wind pressure coefficient in numerical simulation was larger than the value of wind load shape coefficient in the load code． The result has certain reference for typhoon-resistant design of large-span spatial structure for references．
2015, 45(6): 137-144.
doi: 10.13204/j.gyjz201506027
Abstract:
A new type of prestressed cable-braced energy-dissipation frame structure was proposed by adding prestressed cable brace to a high-rise building． This structure could improve lateral resistance and ductility of steel frame effectively，thus resulting in smaller calculation length of columns and less steel-consumption． By using finite element method，the static behavior of cable-braced rigid frame，cable-braced semi-rigid frame and steel frame was analyzed，and the influence law of axial compression ratio on their elastioplasticity behavior，ultimate bearing capacity，failure mechanism，lateral stiffness and ductility etc was studied． The results showed that cable brace could improve the lateral stiffness and bearing capacity of steel frame，more importantly，could also improve its lateral ductility，change failure model，and produce the self-centering function by tensioning frame back to the original location entirely or partly when the load was removed． In addition，with the increase of axial compression ratio， bearing capacities of the three type frames were all decreased，and the ductility of steel frame was also reduced． However，the ductility of cable-braced steel frame was not influenced by the axial compression ratio．
A new type of prestressed cable-braced energy-dissipation frame structure was proposed by adding prestressed cable brace to a high-rise building． This structure could improve lateral resistance and ductility of steel frame effectively，thus resulting in smaller calculation length of columns and less steel-consumption． By using finite element method，the static behavior of cable-braced rigid frame，cable-braced semi-rigid frame and steel frame was analyzed，and the influence law of axial compression ratio on their elastioplasticity behavior，ultimate bearing capacity，failure mechanism，lateral stiffness and ductility etc was studied． The results showed that cable brace could improve the lateral stiffness and bearing capacity of steel frame，more importantly，could also improve its lateral ductility，change failure model，and produce the self-centering function by tensioning frame back to the original location entirely or partly when the load was removed． In addition，with the increase of axial compression ratio， bearing capacities of the three type frames were all decreased，and the ductility of steel frame was also reduced． However，the ductility of cable-braced steel frame was not influenced by the axial compression ratio．
2015, 45(6): 145-149.
doi: 10.13204/j.gyjz201506028
Abstract:
Five typical V-shape concentrically braced steel frames ( CBSF) in zones of seismic intensity VII were designed and their seismic safety was studied according to seismic collapse assessment system of FEMA P695． The results show that the CBSFs based structural influencing coefficientR=3. 2 possess enough anti-collapse capacity， can provide safe room，furthermore，they possess stronger anti-collapse capacity than that ofno callapse in strong earthquake，so that their collapse probability can be accepted under specially strong earthquakes，which can be used in seismic performance-based design．
Five typical V-shape concentrically braced steel frames ( CBSF) in zones of seismic intensity VII were designed and their seismic safety was studied according to seismic collapse assessment system of FEMA P695． The results show that the CBSFs based structural influencing coefficientR=3. 2 possess enough anti-collapse capacity， can provide safe room，furthermore，they possess stronger anti-collapse capacity than that ofno callapse in strong earthquake，so that their collapse probability can be accepted under specially strong earthquakes，which can be used in seismic performance-based design．
2015, 45(6): 150-153.
doi: 10.13204/j.gyjz201506029
Abstract:
The orthogonal tests of 9 basalt fiber ( BF) reinforced concrete filled steel tubular ( BFRCFST) short columns were carried out under axial compression load to investigate the influence of dosages of BF，steel ratio and concrete strength on behavior of BFRCFST short columns． The results indicated that the steel ratio had the most significant effect on bearing capacity of BFRCFST short columns，then dosage of BF，while concrete strength played a comparatively less important part; the bearing capacity of concrete strength C60，dosages of 0. 1% and steel tubular wall thickness 6 mm was higher than that of other level of the same factor． The proper dosages of BF were of advantage to improve the bearing capacity of BFRCFST short columns． BFRCFST short columns showed an increasing trend of the load bearing capacity and ductility with the steel ratio increasing．
The orthogonal tests of 9 basalt fiber ( BF) reinforced concrete filled steel tubular ( BFRCFST) short columns were carried out under axial compression load to investigate the influence of dosages of BF，steel ratio and concrete strength on behavior of BFRCFST short columns． The results indicated that the steel ratio had the most significant effect on bearing capacity of BFRCFST short columns，then dosage of BF，while concrete strength played a comparatively less important part; the bearing capacity of concrete strength C60，dosages of 0. 1% and steel tubular wall thickness 6 mm was higher than that of other level of the same factor． The proper dosages of BF were of advantage to improve the bearing capacity of BFRCFST short columns． BFRCFST short columns showed an increasing trend of the load bearing capacity and ductility with the steel ratio increasing．
2015, 45(6): 154-159.
doi: 10.13204/j.gyjz201506030
Abstract:
This paper analyzed the results of the interface shear strength tests of 47 concrete-filled square steel tube and 18 concrete-filled rectangular steel tube specimens at home and broad． A formulas was proposed for calculating the standard value of interface shear strength． The important role of diaphragms in raising the co-operation of steel tube and concrete was verified by a test in Japan，i． e． the diaphragms could prevent the relative slip between the steel tube and the concrete in it．
This paper analyzed the results of the interface shear strength tests of 47 concrete-filled square steel tube and 18 concrete-filled rectangular steel tube specimens at home and broad． A formulas was proposed for calculating the standard value of interface shear strength． The important role of diaphragms in raising the co-operation of steel tube and concrete was verified by a test in Japan，i． e． the diaphragms could prevent the relative slip between the steel tube and the concrete in it．
2015, 45(6): 160-164.
doi: 10.13204/j.gyjz201506031
Abstract:
Based on tests of five models of steel reinforced recycled concrete frame infilled with recycled concrete hollow blocks under low cyclic reversed loading，their skeleton curves，hysteretic curves，displacement ductility and energy dissipation were analysed，then the test data of feature points in the skeleton curves were obtained． On the basis of the experimental study，the test data were fitted by ORIGIN 8. 0 software and the dimensionless skeleton curve model considering the influence of various parameters，through further regression analysis，the degradation law of unloading rigidity and reloading rigidity was proposed． Ultimately，the restoring force model of steel reinforced recycled concrete frame infilled with recycled concrete hollow blocks was proposed． The comparative analysis of measured skeleton curves and restoring force model showed that this model fit better and could be used for elastic-plastic seismic response analysis of steel reinforced recycled concrete frame infilled with recycled concrete hollow blocks．
Based on tests of five models of steel reinforced recycled concrete frame infilled with recycled concrete hollow blocks under low cyclic reversed loading，their skeleton curves，hysteretic curves，displacement ductility and energy dissipation were analysed，then the test data of feature points in the skeleton curves were obtained． On the basis of the experimental study，the test data were fitted by ORIGIN 8. 0 software and the dimensionless skeleton curve model considering the influence of various parameters，through further regression analysis，the degradation law of unloading rigidity and reloading rigidity was proposed． Ultimately，the restoring force model of steel reinforced recycled concrete frame infilled with recycled concrete hollow blocks was proposed． The comparative analysis of measured skeleton curves and restoring force model showed that this model fit better and could be used for elastic-plastic seismic response analysis of steel reinforced recycled concrete frame infilled with recycled concrete hollow blocks．
2015, 45(6): 165-168.
doi: 10.13204/j.gyjz201506032
Abstract:
In order to study the mechanical performance of truss transmission tower of glass fiber reinforced polymer ( GFRP) ，a full-scale model of a truss transmission tower with a height of 8. 75 m which composed of 1. 25 m high steel earth support and 7. 5 m tower shaft etc，was tested under three different load conditions． Base on the experimental results，it was revealed that the elastic deformation of the GFRP tower was evident due to the relatively low Youngs modulus，yet the maximum stress of the structure under the most unfavorable load was much lower than the design strength of the material． Which showed that the GFＲP tower had relatively good overall mechanical performance，it could satisfy the requirement of the design and use of electric power projects．
In order to study the mechanical performance of truss transmission tower of glass fiber reinforced polymer ( GFRP) ，a full-scale model of a truss transmission tower with a height of 8. 75 m which composed of 1. 25 m high steel earth support and 7. 5 m tower shaft etc，was tested under three different load conditions． Base on the experimental results，it was revealed that the elastic deformation of the GFRP tower was evident due to the relatively low Youngs modulus，yet the maximum stress of the structure under the most unfavorable load was much lower than the design strength of the material． Which showed that the GFＲP tower had relatively good overall mechanical performance，it could satisfy the requirement of the design and use of electric power projects．
2015, 45(6): 169-174.
doi: 10.13204/j.gyjz201506033
Abstract:
In order to avoid local buckling occurring before overall buckling in steel tubular members under pressure， Chinese Code for Design of Steel Structures( GB 500172003) stipulates that diameter-thickness ratio D0 /t should not exceed 100( 235 /fy ) ． But the computing methods of different diameter-thickness ratio on the bearing capacity of steel tube under axial compression are generally given in foreign codes． This paper reviewed each code about the computing method of bearing capacity of steel tube under axial compression，whose result was compared with experimental result and then pointed out the differences among these codes．
In order to avoid local buckling occurring before overall buckling in steel tubular members under pressure， Chinese Code for Design of Steel Structures( GB 500172003) stipulates that diameter-thickness ratio D0 /t should not exceed 100( 235 /fy ) ． But the computing methods of different diameter-thickness ratio on the bearing capacity of steel tube under axial compression are generally given in foreign codes． This paper reviewed each code about the computing method of bearing capacity of steel tube under axial compression，whose result was compared with experimental result and then pointed out the differences among these codes．
2015, 45(6): 175-178.
doi: 10.13204/j.gyjz201506034
Abstract:
The curved beam bridge is widely used in modern city viaduct． Because the complexity of its space stress mechanism，diseases are often found in curved beam bridge which could harm structural safety and serviceability． For this reason，such sort of bridge should be repaired． In this paper，some repair schemes were compared via finite element analysis based on a real bridge project． It is decided that synchronous jack-up system should be used for this project． This system has many advantages，especially when it is used in curved beam bridge． It was discussed the feasibility of using the system for repairing curved bridge project，based on the analysis of synchronous jack-up systems construction process，construction system，correction and bearing-replacement operation process． Through the analysis of monitoring data，the usability of this system was demonstrated in this kind of engineering project． In the end，some recommendations were put forward for popularizing．
The curved beam bridge is widely used in modern city viaduct． Because the complexity of its space stress mechanism，diseases are often found in curved beam bridge which could harm structural safety and serviceability． For this reason，such sort of bridge should be repaired． In this paper，some repair schemes were compared via finite element analysis based on a real bridge project． It is decided that synchronous jack-up system should be used for this project． This system has many advantages，especially when it is used in curved beam bridge． It was discussed the feasibility of using the system for repairing curved bridge project，based on the analysis of synchronous jack-up systems construction process，construction system，correction and bearing-replacement operation process． Through the analysis of monitoring data，the usability of this system was demonstrated in this kind of engineering project． In the end，some recommendations were put forward for popularizing．
2015, 45(6): 179-181.
doi: 10.13204/j.gyjz201506035
Abstract:
By the introduction to Ma Steel Machinery Industrial Park，the process，energy saving and environmental protection，the protection of the ecological environment etc of the overall planning and industrial building design were researched and analyzed． It was pointed out that the development of the architectural technology and material in relevant disciplines should be noticed， steel plant design innovation and breakthrough shall be started from technology，design and management according to technology advances in the upstream， architectural features updated，building materials and technology development，time technology advancement etc．
By the introduction to Ma Steel Machinery Industrial Park，the process，energy saving and environmental protection，the protection of the ecological environment etc of the overall planning and industrial building design were researched and analyzed． It was pointed out that the development of the architectural technology and material in relevant disciplines should be noticed， steel plant design innovation and breakthrough shall be started from technology，design and management according to technology advances in the upstream， architectural features updated，building materials and technology development，time technology advancement etc．
2015, 45(6): 182-185.
doi: 10.13204/j.gyjz201506036
Abstract:
Starting from the construction process of Chinas colleges and universities and the development process of green buildings，it was pointed out that the deficiencies of green energy-saving building concept in the construction of universities and colleges during the end of last century，which resulted in the drawbacks of a large number of existing university buildings，where little attention was paid to the idea of environmentally-friendly design． Taking the design of Henan University of Science and Technology liberal arts teaching group for example，it was elaborated the functions of college teaching group on the environmental space，natural ecology，human needs etc． It was explored and summarized the technical strategies of college teaching group under the evaluation system of green building design．
Starting from the construction process of Chinas colleges and universities and the development process of green buildings，it was pointed out that the deficiencies of green energy-saving building concept in the construction of universities and colleges during the end of last century，which resulted in the drawbacks of a large number of existing university buildings，where little attention was paid to the idea of environmentally-friendly design． Taking the design of Henan University of Science and Technology liberal arts teaching group for example，it was elaborated the functions of college teaching group on the environmental space，natural ecology，human needs etc． It was explored and summarized the technical strategies of college teaching group under the evaluation system of green building design．
2015, 45(6): 186-189.
doi: 10.13204/j.gyjz201506037
Abstract:
BIM ( Building Information Modeling) system is still in the initial stage of development in China，and it has its different data organization and software system in each period of the life cycle of modern building． This makes it more difficult to build a unified information system． How to integrate the effective data，and reflect the architectural information effectively becomes one of the key points of the researches on BIM system． In order to solve the problem of sharing information，applying the field knowledge and making BIM more intelligent，ontology technology was proposed which could be constructed by the standards and experiential knowledge． In this paper，the ontology-based application framework of BIM was proposed，and the way that puts domain ontology into the BIM system was also given． A variety of personalized services can be provided through the combination of the domain ontology and the existing knowledge and data．
BIM ( Building Information Modeling) system is still in the initial stage of development in China，and it has its different data organization and software system in each period of the life cycle of modern building． This makes it more difficult to build a unified information system． How to integrate the effective data，and reflect the architectural information effectively becomes one of the key points of the researches on BIM system． In order to solve the problem of sharing information，applying the field knowledge and making BIM more intelligent，ontology technology was proposed which could be constructed by the standards and experiential knowledge． In this paper，the ontology-based application framework of BIM was proposed，and the way that puts domain ontology into the BIM system was also given． A variety of personalized services can be provided through the combination of the domain ontology and the existing knowledge and data．
