In seismic risk mitigation policies, fragility functions of existing buildings play a fundamental role. In this paper, a procedure to develop analytical fragility curves for Moment Resisting Frame Reinforced Concrete ...In seismic risk mitigation policies, fragility functions of existing buildings play a fundamental role. In this paper, a procedure to develop analytical fragility curves for Moment Resisting Frame Reinforced Concrete buildings is presented. The design of the selected building typologies was performed according to the codes at the time of construction using force-based methods and the state of the practice at the time of construction. A total of 216 building classes were defined, considering different ages, number of storeys, infill panels, plan dimensions, beam stiffness, and concrete strength. The investigated buildings can be considered low-engineered buildings, using no seismic codes or old seismic codes. The seismic capacity of the selected models representing the existing RC buildings has been evaluated through non-linear dynamic simulations. Seismic response has been analyzed, considering various peak and integral intensity measures and various response parameters, such as ductility demands and Interstorey Drift Ratio (IDR). A new relationship among structural performance, damage levels and interstorey drift ratios for each studied type is introduced, which is calibrated using the damage levels described in EMS98. It is important to highlight that in this study, different thresholds of IDR have been associated with different typologies, considering their different ductility member levels after their different structural responses. Fragility Curves (FCs) for the studied structural types are set up, developed and discussed.展开更多
Building collapse mostly can be caused by the loss of loading capacity in a primary structural component,resulting in the failure of surrounding elements,which in turn cause a failure propagation.Progressive collapses...Building collapse mostly can be caused by the loss of loading capacity in a primary structural component,resulting in the failure of surrounding elements,which in turn cause a failure propagation.Progressive collapses may be accidental,due to design deficiencies or errors,material failure or natural phenomenon(e.g.earthquakes)but it can be prevented by upgrade the concrete components’material[1,2].Well-engineered RC buildings generally have a good performance under normal loading conditions.However,faulty design,construction errors,material deterioration,and overloading are always occurred.When part of structure fails,the total load in the whole system will not disappear,which means the load will be redistributed unevenly to the adjacent part of structure.This phenomenon revealed that sustained high stresses in RC elements can lead to catastrophic collapse.Due to very few of papers did the research on the RC elements under high stress level sustained load,relevant experiments should be performed in this area.This paper gives the suggestions about how to apply the load in an experiment if researchers want to know the behavior of elements near to collapse especially focus on RC columns.展开更多
文摘In seismic risk mitigation policies, fragility functions of existing buildings play a fundamental role. In this paper, a procedure to develop analytical fragility curves for Moment Resisting Frame Reinforced Concrete buildings is presented. The design of the selected building typologies was performed according to the codes at the time of construction using force-based methods and the state of the practice at the time of construction. A total of 216 building classes were defined, considering different ages, number of storeys, infill panels, plan dimensions, beam stiffness, and concrete strength. The investigated buildings can be considered low-engineered buildings, using no seismic codes or old seismic codes. The seismic capacity of the selected models representing the existing RC buildings has been evaluated through non-linear dynamic simulations. Seismic response has been analyzed, considering various peak and integral intensity measures and various response parameters, such as ductility demands and Interstorey Drift Ratio (IDR). A new relationship among structural performance, damage levels and interstorey drift ratios for each studied type is introduced, which is calibrated using the damage levels described in EMS98. It is important to highlight that in this study, different thresholds of IDR have been associated with different typologies, considering their different ductility member levels after their different structural responses. Fragility Curves (FCs) for the studied structural types are set up, developed and discussed.
文摘Building collapse mostly can be caused by the loss of loading capacity in a primary structural component,resulting in the failure of surrounding elements,which in turn cause a failure propagation.Progressive collapses may be accidental,due to design deficiencies or errors,material failure or natural phenomenon(e.g.earthquakes)but it can be prevented by upgrade the concrete components’material[1,2].Well-engineered RC buildings generally have a good performance under normal loading conditions.However,faulty design,construction errors,material deterioration,and overloading are always occurred.When part of structure fails,the total load in the whole system will not disappear,which means the load will be redistributed unevenly to the adjacent part of structure.This phenomenon revealed that sustained high stresses in RC elements can lead to catastrophic collapse.Due to very few of papers did the research on the RC elements under high stress level sustained load,relevant experiments should be performed in this area.This paper gives the suggestions about how to apply the load in an experiment if researchers want to know the behavior of elements near to collapse especially focus on RC columns.
