基于修正力插值纤维单元的汶川地震典型高层建筑震害模拟
NUMERICAL SIMULATION FOR A TYPICAL HIGH-RISE BUILDING IN WENCHUAN EARTHQUAKE BASED ON MFBFE SHEAR WALL ELEMENT
-
摘要: 在非线性阶段,剪力墙构件由于其截面高度比较大,受力极为复杂,仍采用平截面假定将会造成较大的误差。考虑截面剪切变形的修正基于力插值纤维单元(MFBFE),其截面不再是平截面,而是曲面,在剪力墙构件的非线性地震反应分析有较高的精度。基于MFBFE单元对汶川地震中破坏严重的都江堰市电信大楼进行逐步增量时程分析(IDA)。分析结果显示底层和9层是薄弱层,而底层由于各指标基本都为最大值,因此将首先出现破坏,这与震害调查结果基本相符。验证了MFBFE单元在实际结构分析中的合理性和可靠性,为高层建筑结构地震灾变行为研究提供参考。Abstract: In shear wall structures, the cross section of shear wall is much wider than that of the beam and the column, thus the assumptions of plane section and zero shear deformation may cause great error in analysis. A modified force-based fiber element (MFBFE) is proposed in this paper, which accounts for the section shear deformation and is capable of accurately predicting the nonlinear deformation of the shear wall. The cross section is a curved surface in the modified element. Nonlinear seismic response analysis of a seriously damage high-rise building by Wenchuan Earthquake in Dujiangyan is performed using the MFBFE shear wall element. Analysis results show that the maximum inter-story drift occurs at the first floor where the damage is serious, which agrees well with the damage survey results. The rationality and reliability of the proposed shear wall element are validated, which provides an effective tool for further research on the seismic behavior of tall buildings.