机构地区: 哈尔滨工业大学土木工程学院
出 处: 《哈尔滨工业大学学报》 2007年第10期1513-1516,共4页
摘 要: 应用等延性位移比谱可以简便有效地估计结构的非弹性位移.在地震动作用下,由于P-Δ效应能够增加结构的非弹性变形和永久变形,因此,研究P-Δ效应对等延性位移比谱的影响具有重要意义.利用四类场地上的344条地震动,分别计算出了考虑及未考虑P-Δ效应的等延性位移比谱,并进行了对比分析,然后根据统计分析的结果,得到了等延性位移比谱考虑P-Δ效应的修正公式.结果表明:P-Δ效应对等延性位移比谱的影响十分可观,并且其影响程度随结构延性的增加而增大,随结构周期的增加而减小;而且当考虑P-Δ效应之后,等位移原理不再适用. For the evaluation of structures with known ductility demands, the constant - ductility displacement ratio spectra that can provide inelastic displacement ratios to estimate maximum lateral inelastic displacement demands from maximum elastic displacement demands is particularly useful. Under the strong ground motions, the inelastic and permanent deformation of structures will increase significantly due to P - △ effect. Thus, the estimation of P - △ effect on constant - ductility inelastic displacement ratios is much important. Inelastic displacement ratio spectra was computed for single - degree - of - freedom systems by considering and not considering P - △ effect for different ductility levels when subjected to 344 earthquake ground motions. Based on statistical analysis, the modified expressions of constant - ductility inelastic displacement ratio spectra for P - △ effect were presented. It is concluded that the P - △ effect on constant - ductility inelastic displacement ratio spectra is significant, and the effect increases with increasing ductility and decreasing structural periods. When the P - △ effect is taken into account, the equal displacement rule for constant - ductility displacement ratio spectra will not be applicable.