基于耐震时程法的羌族碉楼易损性分析

Vulnerability Analysis of Qiang Nationality Blockhouse Based on Endurance Time Analysis

羌族碉楼是羌藏民族的传统民居建筑,极具历史文物价值。近年来地震频发,四川阿坝州、甘孜一带羌族碉楼出现开裂、崩塌等震害,为有效保护该类历史文物建筑,基于《建筑抗震设计规范》(GB 50011—2010)对结构进行修复加固,并通过有限元模型计算、耐震时程分析、Pushover分析等技术手段验证了钢筋笼加固措施的有效性。结果表明:碉楼需要通过加固措施提升结构整体刚度。加固后的碉楼屈服位移有小幅增长,延性提高17.2%,峰值承载力提高37.5%。在各级地震作用下,加固后碉楼出现轻微、中等、严重和完全4种损伤状态的概率明显小于原结构。加固措施对结构延性和承载力的提升具有显著效果,也能有效降低结构易损性,加固措施合理,可为同类型工程提供参考依据。

The Qiang nationality blockhouse is a traditional residential building of Qiang and Tibetan nationality,which is of great historical and cultural value.In recent years,earthquakes have occurred frequently,and Qiang blockhouses in Aba Prefecture and Ganzi area of Sichuan Province have cracks,collapses and other diseases.In order to effectively protect this kind of historical and cultural relics buildings,the structure was repaired and strengthened based on Code for Seismic Design of Buildings(GB 50011—2010),and the effectiveness of the reinforcement measures was verified by means of finite element model calculation,endurance time analysis,pushover analysis and other technical means.The results show that the blockhouse is a flexible structure,and the overall stiffness of the structure needs to be improved through reinforcement measures.The yield displacement of the strengthened blockhouse increases slightly,the ductility increases by 19.5%,and the peak bearing capacity increases by 37.5%.Under the action of earthquakes at all levels,the probability of four damage states of the strengthened blockhouse is significantly less than that of the original structure.The reinforcement measures can not only improve the ductility and bearing capacity of the structure,but also effectively reduce the vulnerability of the structure.The reinforcement measures are reasonable and can provide reference basis for similar projects.