The aspect ratio of the structure has a significant impact on the overall stability of the ultra high-rise building. A large aspect ratio of the structure increases the risk of overturning and reduces the lateral stif...The aspect ratio of the structure has a significant impact on the overall stability of the ultra high-rise building. A large aspect ratio of the structure increases the risk of overturning and reduces the lateral stiffness of the structure, leading to significant tensile and compressive stresses in the isolated bearings. To study the effect of aspect ratio on the seismic response and overturning resistance of a new staggered story isolated structure, three models with different aspect ratios were established. Nonlinear time-history analysis of the three models was conducted using ETABS finite element software. The results indicate that the overturning moment and overturning resistance moment of the superstructure in the new staggered story isolated structure increase with an increasing aspect ratio. However, the increase in the overturning moment of the superstructure is much greater than the increase in the overturning resistance moment, resulting in a decrease in the overturning resistance ratio of the superstructure with an increasing aspect ratio. The overturning moment and overturning resistance moment of the substructure in the new staggered story isolated structure decrease with an increasing aspect ratio. However, the decrease in the overturning moment of the substructure is greater than the decrease in the overturning resistance moment, leading to an increase in the overturning resistance ratio of the substructure with an increasing aspect ratio. The decrease in the overturning resistance ratio of the superstructure in the new staggered story isolated structure is much greater than the increase in the overturning resistance ratio of the substructure. Therefore, as the aspect ratio of the overall structure increases, the overturning resistance ratio of the superstructure and the entire structure decreases.展开更多
A new staggered isolated system developed from the mid-story isolated system is the new staggered story isolated system. There are not many studies on this structure currently. In this study, an 18-story new staggered...A new staggered isolated system developed from the mid-story isolated system is the new staggered story isolated system. There are not many studies on this structure currently. In this study, an 18-story new staggered story isolated system model is established using SAP2000. The dynamic nonlinear dynamic alternate method is used to analyze the structure against progressive collapse. Results show that the structure has good resistance to progressive collapse, and there is no progressive collapse under each working condition. The progressive collapse does not occur for the case of removing only one vertical structural member of the new staggered of isolated system. The side column has big influence on this isolated structures’ progressive collapse;the removal of vertical structural member of the isolation layer has less impact on the structure than the removal of the bottom vertical structural member. After the removing of the member, the internal force of the structure will be redistributed, and the axial force of the adjacent columns will change obviously, showing a trend of “near large and far small”.展开更多
文摘The aspect ratio of the structure has a significant impact on the overall stability of the ultra high-rise building. A large aspect ratio of the structure increases the risk of overturning and reduces the lateral stiffness of the structure, leading to significant tensile and compressive stresses in the isolated bearings. To study the effect of aspect ratio on the seismic response and overturning resistance of a new staggered story isolated structure, three models with different aspect ratios were established. Nonlinear time-history analysis of the three models was conducted using ETABS finite element software. The results indicate that the overturning moment and overturning resistance moment of the superstructure in the new staggered story isolated structure increase with an increasing aspect ratio. However, the increase in the overturning moment of the superstructure is much greater than the increase in the overturning resistance moment, resulting in a decrease in the overturning resistance ratio of the superstructure with an increasing aspect ratio. The overturning moment and overturning resistance moment of the substructure in the new staggered story isolated structure decrease with an increasing aspect ratio. However, the decrease in the overturning moment of the substructure is greater than the decrease in the overturning resistance moment, leading to an increase in the overturning resistance ratio of the substructure with an increasing aspect ratio. The decrease in the overturning resistance ratio of the superstructure in the new staggered story isolated structure is much greater than the increase in the overturning resistance ratio of the substructure. Therefore, as the aspect ratio of the overall structure increases, the overturning resistance ratio of the superstructure and the entire structure decreases.
文摘A new staggered isolated system developed from the mid-story isolated system is the new staggered story isolated system. There are not many studies on this structure currently. In this study, an 18-story new staggered story isolated system model is established using SAP2000. The dynamic nonlinear dynamic alternate method is used to analyze the structure against progressive collapse. Results show that the structure has good resistance to progressive collapse, and there is no progressive collapse under each working condition. The progressive collapse does not occur for the case of removing only one vertical structural member of the new staggered of isolated system. The side column has big influence on this isolated structures’ progressive collapse;the removal of vertical structural member of the isolation layer has less impact on the structure than the removal of the bottom vertical structural member. After the removing of the member, the internal force of the structure will be redistributed, and the axial force of the adjacent columns will change obviously, showing a trend of “near large and far small”.
