MPA方法与定侧力模式Pushover方法的准确性对比研究

Pushover方法作为一种简化的评价结构抗震性能和验算结构弹塑性变形的方法，近年来得到了广泛应用。但由于Pushover方法只考虑第一振型，无法反映结构高阶振型的影响，因此又发展了基于振型分解反应谱法的多模态Pushover方法（Modal Pushover Analysis，MPA），但MPA方法与Pushover方法分析结果的准确性和对比研究目前没有见到。为合理采用MPA方法与Pushover方法，本文以逐步增量弹塑性时程分析结果为基准，通过两个普通的六层和十层钢筋混凝土框架结构，对MPA方法和不同侧力模式的Pushover方法的分析结果进行了对比研究。研究表明，与Pushover方法相比，MPA方法对结构最大弹塑性顶点位移响应的预测具有较高精度，但对结构最大层间位移的预测误差仍较大，有必要作进一步深入研究。

Comparative Evaluation of Pushover Analysis and Modal Pushover Analysis with invariant spatial earthquake load

Nonlinear static analysis procedure is now widely used as a simplified effective method for estimating the inelastic responses of structures under severe ground motions. Based on structural dynamics theory, the modal pushover analysis (MPA) procedure is proposed to consider effect of the higher structural response modes, which is equivalent to standard response spectrum analysis for elastic systems. Although the MPA procedure is common in structural engineering practice, there are few researches on comparative evaluation of pushover analysis and MPA procedure with invariant spatial earthquake load. Herein, MPA and pushover procedures are estimated to compare with incremental nonlinear dynamic time history analysis with invariant spatial earthquake load for a six-story and a ten-story. It is indicated that the both pushover and MPA procedures give good prediction for inelastic roof displacements, especially the MPA procedure. Whereas, the estimation of the maximum story drift of structure needs to be improved and requires further more investigation.