This paper presents some methods that the standard acceleration design response spectra derived from the present China code for seismic design of buildings are transformed into the seismic demand spectra, and that the...This paper presents some methods that the standard acceleration design response spectra derived from the present China code for seismic design of buildings are transformed into the seismic demand spectra, and that the base shear force-roof displacement curve of structure is converted to the capacity spectrum of an equivalent single-degree-of-freedom (SDOF) system. The capacity spectrum method (CSM) is programmed by means of MATLABT.0 computer language. A dual lateral force resisting system of 10-story steel frame-steel plate shear walls (SPSW) is designed according to the corresponding China design codes. The base shear force-roof displacement curve of structure subjected to the monotonic increasing lateral inverse triangular load is obtained by applying the equivalent strip model to stimulate SPSW and by using the finite element analysis software SAP2000 to make Pushover analysis. The seismic performance of this dual system subjected to three different conditions, i.e. the 8-intensity frequently occurred earthquake, fortification earthquake and seldom occurred earthquake, is evaluated by CSM program. The excessive safety of steel frame-SPSW system designed according to the present China design codes is pointed out and a new design method is suggested.展开更多
Based on the concept of stiffness degradation, a damage index of the whole frame and the storey is proposed for the frame seismic performance evaluation. The index is compatible with the non-linear static analysis (e...Based on the concept of stiffness degradation, a damage index of the whole frame and the storey is proposed for the frame seismic performance evaluation. The index is compatible with the non-linear static analysis (e. g. the pushover analysis), and the structural damage is considered via plastic hinges. Simultaneously, a practical approach is developed to obtain the relationships between the proposed index and earthquake intensities based on the capacity spectrum method. The proposed index is then illustrated through two low-rise reinforced concrete frames, and it is also compared with some other indices. The results indicate that the proposed index is on the safe side and not sensitive to the lateral load pattern. The storey index is helpful to reflect the storey damage and to uncover the position of the weak storey. Finally, the relationship between performance levels and damage index values is also proposed through statistical analysis for the performance-based seismic evaluation.展开更多
Evaluation of structural performance under seismic excitations from low intensity to high intensity is essential to verify the seismic resistant capacity of a structure, and usually carried out by the incremental dyna...Evaluation of structural performance under seismic excitations from low intensity to high intensity is essential to verify the seismic resistant capacity of a structure, and usually carried out by the incremental dynamic analysis (IDA) method or pushover method. The recently developed endurance time (ET) method is another method that uses dynamic pushover excitations, i.e., endurance time acceleration function, to obtain results similar to those obtained by IDA or pushover methods with low computational cost and acceptable accuracy. This study proposes an improvement on the ET method by considering more restrictions for both the elastic and inelastic response spectra in the generation procedure, and by specifying a target duration. Four reinforced concrete frame structures with 4, 8, 12, and 16 stories are adopted to verify the accuracy of the improved method. Comparison of the results obtained by the proposed method, the ET method and the IDA method shows that the improved method has a higher accuracy than the ET method. For evaluation of structural responses under specifi c ground motion intensity, which is typically required in seismic design codes, the results obtained by the proposed method are compared with fi ve commonly used ground motion selection methods, and shows the proposed method provides acceptable accuracy for engineering applications.展开更多
The Code for Seismic Design of Buildings(GB50011-2010)in 2016 and the method of seismic performance-based design for high-rise buildings in the Guide for Performance-based Design of High-Rise Buildings(TBI2017)are com...The Code for Seismic Design of Buildings(GB50011-2010)in 2016 and the method of seismic performance-based design for high-rise buildings in the Guide for Performance-based Design of High-Rise Buildings(TBI2017)are compared.In view of the characteristics and limitations of the seismic performance index set by the Sino-US seismic code,a“three-index”performance index system and evaluation process considering the displacement angle of the structural interlayer,the plastic damage degree of components and the plastic strain of material is put forward;combining the example of time-history analysis of a out-of-code high-rise building under the rare earthquakes is verified.The results show that the method of seismic performance evaluation by using deformation control index in Sino-US seismic code is relatively simple;however,both are lacking in the setting of specific components and the whole structure level respectively.The"three-index"system can comprehensively and quantitatively evaluate the seismic performance of out-of-code high-rise buildings.展开更多
With increasing demand to reduce the carbon emission of buildings,it is crucial to quantify the life cycle envi-ronmental impact of new buildings,including the environmental impact due to natural hazards,such as earth...With increasing demand to reduce the carbon emission of buildings,it is crucial to quantify the life cycle envi-ronmental impact of new buildings,including the environmental impact due to natural hazards,such as earth-quakes.This study presents a novel comprehensive probabilistic framework to quantify the environmental impact of buildings,including uncertainties in the material extraction and production,transportation,construction,seis-mic exposure and aging(including deterioration),and end-of-life stages.The developed framework is used to quantify the environmental impact of a 3-story residential building located in Vancouver,Canada.The results show that there is a significant variation in the environmental impact of the prototype building in each stage of the life cycle assessment.If the prototype building is hit by the design level earthquake,it is expected that the median environmental impact of the prototype will be further increased by 42%.In addition,by accounting for the probability of occurrence of different earthquakes within a 50-year design life of the prototype building,the earthquake related damage will result in an additional 5%of the initial carbon emission of the building.This shows the importance of including earthquake hazard and deterioration in whole building life cycle assessments.展开更多
为了对基于性能的结构抗震设计提供决策依据,提出可恢复指标对结构不同损伤机制的安全、经济和可恢复性进行对比评价.以体系恢复力(resilience of system)为基础,阐述给定烈度区下单体结构可恢复指标的计算方法和流程;对5种典型损伤机制...为了对基于性能的结构抗震设计提供决策依据,提出可恢复指标对结构不同损伤机制的安全、经济和可恢复性进行对比评价.以体系恢复力(resilience of system)为基础,阐述给定烈度区下单体结构可恢复指标的计算方法和流程;对5种典型损伤机制的RC框架结构,进行易损性分析和恢复力参数计算,得到结构可恢复指标;分析可恢复指标对各主要恢复力参数的敏感性,提出修正的给定烈度区下结构可恢复指标计算方法.结果表明:可恢复指标能够较全面地涵盖结构地震损失相关因素,体现结构的恢复力(即安全、经济和可恢复性);修正的结构可恢复指标能够较好地区分各损伤机制的恢复力,符合已有研究对各损伤机制优劣的定性判别.展开更多
基金Project (No. 50578099) supported by the National Natural ScienceFoundation of China
文摘This paper presents some methods that the standard acceleration design response spectra derived from the present China code for seismic design of buildings are transformed into the seismic demand spectra, and that the base shear force-roof displacement curve of structure is converted to the capacity spectrum of an equivalent single-degree-of-freedom (SDOF) system. The capacity spectrum method (CSM) is programmed by means of MATLABT.0 computer language. A dual lateral force resisting system of 10-story steel frame-steel plate shear walls (SPSW) is designed according to the corresponding China design codes. The base shear force-roof displacement curve of structure subjected to the monotonic increasing lateral inverse triangular load is obtained by applying the equivalent strip model to stimulate SPSW and by using the finite element analysis software SAP2000 to make Pushover analysis. The seismic performance of this dual system subjected to three different conditions, i.e. the 8-intensity frequently occurred earthquake, fortification earthquake and seldom occurred earthquake, is evaluated by CSM program. The excessive safety of steel frame-SPSW system designed according to the present China design codes is pointed out and a new design method is suggested.
基金The National Basic Research Program of China(973 Program)(No.2007CB714200)
文摘Based on the concept of stiffness degradation, a damage index of the whole frame and the storey is proposed for the frame seismic performance evaluation. The index is compatible with the non-linear static analysis (e. g. the pushover analysis), and the structural damage is considered via plastic hinges. Simultaneously, a practical approach is developed to obtain the relationships between the proposed index and earthquake intensities based on the capacity spectrum method. The proposed index is then illustrated through two low-rise reinforced concrete frames, and it is also compared with some other indices. The results indicate that the proposed index is on the safe side and not sensitive to the lateral load pattern. The storey index is helpful to reflect the storey damage and to uncover the position of the weak storey. Finally, the relationship between performance levels and damage index values is also proposed through statistical analysis for the performance-based seismic evaluation.
基金National Key R&D Program of China under Grant No.2016YFC0701500National Natural Science Foundation of China under Grant No.51578202
文摘Evaluation of structural performance under seismic excitations from low intensity to high intensity is essential to verify the seismic resistant capacity of a structure, and usually carried out by the incremental dynamic analysis (IDA) method or pushover method. The recently developed endurance time (ET) method is another method that uses dynamic pushover excitations, i.e., endurance time acceleration function, to obtain results similar to those obtained by IDA or pushover methods with low computational cost and acceptable accuracy. This study proposes an improvement on the ET method by considering more restrictions for both the elastic and inelastic response spectra in the generation procedure, and by specifying a target duration. Four reinforced concrete frame structures with 4, 8, 12, and 16 stories are adopted to verify the accuracy of the improved method. Comparison of the results obtained by the proposed method, the ET method and the IDA method shows that the improved method has a higher accuracy than the ET method. For evaluation of structural responses under specifi c ground motion intensity, which is typically required in seismic design codes, the results obtained by the proposed method are compared with fi ve commonly used ground motion selection methods, and shows the proposed method provides acceptable accuracy for engineering applications.
文摘The Code for Seismic Design of Buildings(GB50011-2010)in 2016 and the method of seismic performance-based design for high-rise buildings in the Guide for Performance-based Design of High-Rise Buildings(TBI2017)are compared.In view of the characteristics and limitations of the seismic performance index set by the Sino-US seismic code,a“three-index”performance index system and evaluation process considering the displacement angle of the structural interlayer,the plastic damage degree of components and the plastic strain of material is put forward;combining the example of time-history analysis of a out-of-code high-rise building under the rare earthquakes is verified.The results show that the method of seismic performance evaluation by using deformation control index in Sino-US seismic code is relatively simple;however,both are lacking in the setting of specific components and the whole structure level respectively.The"three-index"system can comprehensively and quantitatively evaluate the seismic performance of out-of-code high-rise buildings.
文摘With increasing demand to reduce the carbon emission of buildings,it is crucial to quantify the life cycle envi-ronmental impact of new buildings,including the environmental impact due to natural hazards,such as earth-quakes.This study presents a novel comprehensive probabilistic framework to quantify the environmental impact of buildings,including uncertainties in the material extraction and production,transportation,construction,seis-mic exposure and aging(including deterioration),and end-of-life stages.The developed framework is used to quantify the environmental impact of a 3-story residential building located in Vancouver,Canada.The results show that there is a significant variation in the environmental impact of the prototype building in each stage of the life cycle assessment.If the prototype building is hit by the design level earthquake,it is expected that the median environmental impact of the prototype will be further increased by 42%.In addition,by accounting for the probability of occurrence of different earthquakes within a 50-year design life of the prototype building,the earthquake related damage will result in an additional 5%of the initial carbon emission of the building.This shows the importance of including earthquake hazard and deterioration in whole building life cycle assessments.
文摘为了对基于性能的结构抗震设计提供决策依据,提出可恢复指标对结构不同损伤机制的安全、经济和可恢复性进行对比评价.以体系恢复力(resilience of system)为基础,阐述给定烈度区下单体结构可恢复指标的计算方法和流程;对5种典型损伤机制的RC框架结构,进行易损性分析和恢复力参数计算,得到结构可恢复指标;分析可恢复指标对各主要恢复力参数的敏感性,提出修正的给定烈度区下结构可恢复指标计算方法.结果表明:可恢复指标能够较全面地涵盖结构地震损失相关因素,体现结构的恢复力(即安全、经济和可恢复性);修正的结构可恢复指标能够较好地区分各损伤机制的恢复力,符合已有研究对各损伤机制优劣的定性判别.