The Fort d’Issy-Vanves-Clamart(FIVC)braced excavation in France is analyzed to provide insights into the geotechnical serviceability assessment of excavations at great depth within deterministic and probabilistic fra...The Fort d’Issy-Vanves-Clamart(FIVC)braced excavation in France is analyzed to provide insights into the geotechnical serviceability assessment of excavations at great depth within deterministic and probabilistic frameworks.The FIVC excavation is excavated at 32 m below the ground surface in Parisian sedimentary basin and a plane-strain finite element analysis is implemented to examine the wall deflections and ground surface settlements.A stochastic finite element method based on the polynomial chaos Kriging metamodel(MSFEM)is then proposed for the probabilistic analyses.Comparisons with field measurements and former studies are carried out.Several academic cases are then conducted to investigate the great-depth excavation stability regarding the maximum horizontal wall deflection and maximum ground surface settlement.The results indicate that the proposed MSFEM is effective for probabilistic analyses and can provide useful insights for the excavation design and construction.A sensitivity analysis for seven considered random parameters is then implemented.The soil friction angle at the excavation bottom layer is the most significant one for design.The soil-wall interaction effects on the excavation stability are also given.展开更多
This paper presents the restraining moments of outriggers acting on the core wall and the equation of the horizontal top deflection based on a simplified outrigger model. The deformation compatibility conditions betwe...This paper presents the restraining moments of outriggers acting on the core wall and the equation of the horizontal top deflection based on a simplified outrigger model. The deformation compatibility conditions between outriggers and core wall as well as the finite rigidities of outriggers are also considered. One case study was carried out to analyze the horizontal top deflection and the mutation of the restraining moments caused by the variation of outrigger location. The results showed that the method adopted in the paper is simple and reasonable. Some conclusions are valuable to the safety design of high-rise building structures.展开更多
This study analyzes the feasibility of the use of cross-laminated timber(CLT)as a load-bearing structural element in a 40-story building based on Chinese design requirements.The proposed design of the high-rise concre...This study analyzes the feasibility of the use of cross-laminated timber(CLT)as a load-bearing structural element in a 40-story building based on Chinese design requirements.The proposed design of the high-rise concrete-CLT building utilizes the core-outrigger system.Concrete is used for the central core and outriggers,and CLT is used for the rest of the structure of the building.Finite element models with different types of connections were developed using SAP2000 to analyze the lateral behavior of the building under wind action.The finite element models with rigid connections deduce the wind load distributions on individual structural elements,which determine the total number and the stiffness of fasteners of the CLT panels.Accordingly,spring links with equivalent stiffness that simulate the mechanical fasteners were employed in SAP2000.The results indicate that CLT increases the lateral flexibility of the building.A closed concrete core was substituted by two half cores to measure the requirement of the maximum lateral deflection.However,the acceleration at the building top still exceeded the limitation prescribed in Chinese Code JGJ 3-2010 owing to the lightweight of CLT and decreased stiffness of the hybrid building.To restrict this top acceleration within the limit,further approaches to increase the stiffness in the weak direction of the building are required.Methods such as the modification of the floor layout,increase in the thickness of walls,and addition of extra damping capacity should be considered and verified in the future.展开更多
基金gratefully the China Scholarship Council for providing a PhD Scholarship(CSC No.201906690049).
文摘The Fort d’Issy-Vanves-Clamart(FIVC)braced excavation in France is analyzed to provide insights into the geotechnical serviceability assessment of excavations at great depth within deterministic and probabilistic frameworks.The FIVC excavation is excavated at 32 m below the ground surface in Parisian sedimentary basin and a plane-strain finite element analysis is implemented to examine the wall deflections and ground surface settlements.A stochastic finite element method based on the polynomial chaos Kriging metamodel(MSFEM)is then proposed for the probabilistic analyses.Comparisons with field measurements and former studies are carried out.Several academic cases are then conducted to investigate the great-depth excavation stability regarding the maximum horizontal wall deflection and maximum ground surface settlement.The results indicate that the proposed MSFEM is effective for probabilistic analyses and can provide useful insights for the excavation design and construction.A sensitivity analysis for seven considered random parameters is then implemented.The soil friction angle at the excavation bottom layer is the most significant one for design.The soil-wall interaction effects on the excavation stability are also given.
基金Project supported by the National Natural Science Foundation of China (No. 50378041) and the Specialized Research Fund for theDoctoral Program of Higher Education (No. 20030487016), China
文摘This paper presents the restraining moments of outriggers acting on the core wall and the equation of the horizontal top deflection based on a simplified outrigger model. The deformation compatibility conditions between outriggers and core wall as well as the finite rigidities of outriggers are also considered. One case study was carried out to analyze the horizontal top deflection and the mutation of the restraining moments caused by the variation of outrigger location. The results showed that the method adopted in the paper is simple and reasonable. Some conclusions are valuable to the safety design of high-rise building structures.
文摘This study analyzes the feasibility of the use of cross-laminated timber(CLT)as a load-bearing structural element in a 40-story building based on Chinese design requirements.The proposed design of the high-rise concrete-CLT building utilizes the core-outrigger system.Concrete is used for the central core and outriggers,and CLT is used for the rest of the structure of the building.Finite element models with different types of connections were developed using SAP2000 to analyze the lateral behavior of the building under wind action.The finite element models with rigid connections deduce the wind load distributions on individual structural elements,which determine the total number and the stiffness of fasteners of the CLT panels.Accordingly,spring links with equivalent stiffness that simulate the mechanical fasteners were employed in SAP2000.The results indicate that CLT increases the lateral flexibility of the building.A closed concrete core was substituted by two half cores to measure the requirement of the maximum lateral deflection.However,the acceleration at the building top still exceeded the limitation prescribed in Chinese Code JGJ 3-2010 owing to the lightweight of CLT and decreased stiffness of the hybrid building.To restrict this top acceleration within the limit,further approaches to increase the stiffness in the weak direction of the building are required.Methods such as the modification of the floor layout,increase in the thickness of walls,and addition of extra damping capacity should be considered and verified in the future.