加固砌体结构试验破坏评估与模拟

Evaluation and simulation of experimental damage of a retrofitted masonry structure

本文对某二层足尺采用后张预应力技术加固的砌体结构进行拟静力试验,针对结构在不同振幅下的损伤情况,利用《建(构)筑物地震破坏等级划分(GB/T 24335-2009)》标准进行了损伤判别,得到了不同破坏等级与层间位移角的对应关系,即1/3 000~1/1 000为轻微破坏,1/1 000~1/500为中等破坏,1/500~1/300为严重破坏,>1/300为倒毁状态。为了检验后张预应力技术的加固效果,采用有限元软件对其进行数值模拟,通过试验结果验证了模拟的正确性,然后去除预应力模拟了未加固结构的拟静力试验,结果表明预应力加固技术对结构刚度贡献不大,而对强度有30%的提高。

A full-scale two-story masonry building retrofitted by post-tensioned steel rebars was tested quasi-statically. The damage was evaluated by using the standard 'Classification of earthquake damage to buildings and special structures( GB / T24335- 2009) 'with respect to each loading amplitude. The damage was classified as slight damage: 1 /3 000 ~ 1 /1 000; medium damage: 1 /1 000 ~ 1 /500; severe damage: 1 /500 ~ 1 /300; and collapse: > 1 /300. Finally,a numerical finite element model was developed to evaluate the retrofitting effect. First the model was calibrated by use of the experimental results. Then the post tension elements were removed to simulate the non-retrofitted structure. It is concluded that the post-tension retrofitting technology has limited influence on the stiffness,while the strength is enhanced by 30%.