Assessing the potential damage caused by earthquakes is crucial for a community’s emergency response.In this study,four machine learning(ML)methods—random forest,extremely randomized trees,AdaBoost(AB),and gradient ...Assessing the potential damage caused by earthquakes is crucial for a community’s emergency response.In this study,four machine learning(ML)methods—random forest,extremely randomized trees,AdaBoost(AB),and gradient boosting(GB)—were employed to develop prediction models for the damage potential of the mainshock(DIMS)and mainshock–aftershock sequences(DIMA).Building structures were modeled using eight single-degree-of-freedom(SDOF)systems with different hysteretic rules.A set of 662 recorded mainshock–aftershock(MS-AS)ground motions was selected from the PEER database.Seven intensity measures(IMs)were chosen to represent the characteristics of the mainshock and aftershock.The results revealed that the selected ML methods can well predict the structural damage potential of the SDOF systems,except for the AB method.The GB model exhibited the best performance,making it the recommended choice for predicting DIMS and DIMA among the four ML models.Additionally,the impact of input variables in the prediction was investigated using the shapley additive explanations(SHAP)method.The high-correlation variables were sensitive to the structural period(T).At T=1.0 s,the mainshock peak ground velocity(PGVM)and aftershock peak ground displacement(PGDA)significantly influenced the prediction of DIMA.When T increased to 5.0 s,the primary high-correlation factor of the mainshock IMs changed from PGVM to the mainshock peak ground displacement(PGDM);however,the highcorrelation variable of the aftershock IMs remained PGDA.The high-correlation factors for DIMS showed trends similar to those of DIMA.Finally,a table summarizing the first and second high-correlation variables for predicting DIMS and DIMA were provided,offering a valuable reference for parameter selection in seismic damage prediction for mainshock–aftershock sequences.展开更多
As a novel coupling beam for coupled shear wall structures,the bending-type frictional steel truss coupling beam(BFTCB)concentrates the deformation and energy dissipation in friction dampers at the bottom chord,allowi...As a novel coupling beam for coupled shear wall structures,the bending-type frictional steel truss coupling beam(BFTCB)concentrates the deformation and energy dissipation in friction dampers at the bottom chord,allowing the main body to remain elastic during earthquakes.As the preparatory work for resilient structure design based on the BFTCB,this work concentrates on developing the hysteretic model for BFTCB.Firstly,the BFTCB stiffness-strength decoupling mechanism was introduced,i.e.,the shear strength is provided by friction dampers while webs control its initial stiffness.Secondly,a hysteretic model that reflects the BFTCB two-stage sliding characteristic was proposed.The model consists of a trilinear backbone curve and the unloading and reverse loading rules.The model has eight control parameters,of which two core parameters(initial stiffness and limiting shear strength)are derived from the BFTCB stiffness-strength decoupling mechanism,whereas the remaining parameters are obtained by theoretical analysis and empirical calibration.The hysteretic model was then compared with the test curves and demonstrated good accuracy.Finally,a series of FE prototypes of BFTCB with different design stiffnesses and strengths was adopted to verify the hysteretic model.The results showed that the proposed model fitted well with the FE prototypes,indicating its applicability to BFTCB with varying core design parameters.Therefore,the hysteretic model can be adopted for BFTCB to support the resilient shear wall structure design.展开更多
The ductile design principle has been widely adopted in seismic design of structures,so the main structural components are designed to have the dual functions of bearing and energy dissipation under the earthquake.In ...The ductile design principle has been widely adopted in seismic design of structures,so the main structural components are designed to have the dual functions of bearing and energy dissipation under the earthquake.In recent years,the intensity of major earthquakes occurred in China,Chile,New Zealand,and Japan had reached or exceeded the design level of the maximum credible earthquake.In most cases,the designed structures did not collapse and the casualties were small.However,many structures were seriously damaged and must be overhauled or rebuilt,resulting in huge economic losses.Therefore,researchers have paid more attention to the seismic resilient structures.The shear wall can provide an efficient lateral force resisting capacity and has a wide range of applications in building structures.This review firstly summarized the research advances of seismic resilient shear wall structures,mainly from three aspects:high-performance materials,replaceable components,and hybrid structural systems;then,the development of seismic performance analysis,design methods,and engineering applications of seismic resilient shear wall structures were presented;finally,the key issues that need to be explored in the future research were discussed,which was helpful for the wide application of seismic resilient shear wall structures.展开更多
基金China Postdoctoral Science Foundation under Grant No.2022M710333the Beijing Postdoctoral Research Foundation under Grant No.2023-zz-141the National Natural Science Foundation of China under Grant Nos.52278492 and 52078176。
文摘Assessing the potential damage caused by earthquakes is crucial for a community’s emergency response.In this study,four machine learning(ML)methods—random forest,extremely randomized trees,AdaBoost(AB),and gradient boosting(GB)—were employed to develop prediction models for the damage potential of the mainshock(DIMS)and mainshock–aftershock sequences(DIMA).Building structures were modeled using eight single-degree-of-freedom(SDOF)systems with different hysteretic rules.A set of 662 recorded mainshock–aftershock(MS-AS)ground motions was selected from the PEER database.Seven intensity measures(IMs)were chosen to represent the characteristics of the mainshock and aftershock.The results revealed that the selected ML methods can well predict the structural damage potential of the SDOF systems,except for the AB method.The GB model exhibited the best performance,making it the recommended choice for predicting DIMS and DIMA among the four ML models.Additionally,the impact of input variables in the prediction was investigated using the shapley additive explanations(SHAP)method.The high-correlation variables were sensitive to the structural period(T).At T=1.0 s,the mainshock peak ground velocity(PGVM)and aftershock peak ground displacement(PGDA)significantly influenced the prediction of DIMA.When T increased to 5.0 s,the primary high-correlation factor of the mainshock IMs changed from PGVM to the mainshock peak ground displacement(PGDM);however,the highcorrelation variable of the aftershock IMs remained PGDA.The high-correlation factors for DIMS showed trends similar to those of DIMA.Finally,a table summarizing the first and second high-correlation variables for predicting DIMS and DIMA were provided,offering a valuable reference for parameter selection in seismic damage prediction for mainshock–aftershock sequences.
基金supported by the Scientific Research Fund of MultiFunctional Shaking Tables Laboratory of Beijing University of Civil Engineering and Architecture(2022MFSTL06)Science&Technology Foundation of Liaoning Province,China:General Program(2021-MS131).
文摘As a novel coupling beam for coupled shear wall structures,the bending-type frictional steel truss coupling beam(BFTCB)concentrates the deformation and energy dissipation in friction dampers at the bottom chord,allowing the main body to remain elastic during earthquakes.As the preparatory work for resilient structure design based on the BFTCB,this work concentrates on developing the hysteretic model for BFTCB.Firstly,the BFTCB stiffness-strength decoupling mechanism was introduced,i.e.,the shear strength is provided by friction dampers while webs control its initial stiffness.Secondly,a hysteretic model that reflects the BFTCB two-stage sliding characteristic was proposed.The model consists of a trilinear backbone curve and the unloading and reverse loading rules.The model has eight control parameters,of which two core parameters(initial stiffness and limiting shear strength)are derived from the BFTCB stiffness-strength decoupling mechanism,whereas the remaining parameters are obtained by theoretical analysis and empirical calibration.The hysteretic model was then compared with the test curves and demonstrated good accuracy.Finally,a series of FE prototypes of BFTCB with different design stiffnesses and strengths was adopted to verify the hysteretic model.The results showed that the proposed model fitted well with the FE prototypes,indicating its applicability to BFTCB with varying core design parameters.Therefore,the hysteretic model can be adopted for BFTCB to support the resilient shear wall structure design.
基金supported by the Scientific Research Fund of Multi-Functional Shaking Tables Laboratory of Beijing University of Civil Engineering and Architecture(Grant No.2021MFSTL01)the National Natural Science Foundation of China(Grant No.52108440)+2 种基金the Natural Science Foundation of Jiangsu Province(Grant No.BK20210253)the Project Funded by China Postdoctoral Science Foundation(Grant No.2021M690620)Jiangsu Planned Projects for Postdoctoral Research Funds(Grant No.2021K263B)。
文摘The ductile design principle has been widely adopted in seismic design of structures,so the main structural components are designed to have the dual functions of bearing and energy dissipation under the earthquake.In recent years,the intensity of major earthquakes occurred in China,Chile,New Zealand,and Japan had reached or exceeded the design level of the maximum credible earthquake.In most cases,the designed structures did not collapse and the casualties were small.However,many structures were seriously damaged and must be overhauled or rebuilt,resulting in huge economic losses.Therefore,researchers have paid more attention to the seismic resilient structures.The shear wall can provide an efficient lateral force resisting capacity and has a wide range of applications in building structures.This review firstly summarized the research advances of seismic resilient shear wall structures,mainly from three aspects:high-performance materials,replaceable components,and hybrid structural systems;then,the development of seismic performance analysis,design methods,and engineering applications of seismic resilient shear wall structures were presented;finally,the key issues that need to be explored in the future research were discussed,which was helpful for the wide application of seismic resilient shear wall structures.
