泸定6.8级地震城镇居住建筑典型震害及启示

Typical seismic damage of urban residential buildings in Ms6.8 Luding earthquake and its enlightenment

为分析泸定68级地震中城镇居住建筑的破坏情况,对位于震中磨西镇及周边城镇居住建筑的典型震害进行调查,总结了城镇居住建筑中框架结构及砌体结构的震害特征,详细介绍了一栋采用框架结构的高层住宅及一栋采用砌体结构的多层员工宿舍的破坏情况,并分析破坏原因。调查与分析结果表明:本次地震中,框架结构和砌体结构破坏普遍在底层更严重;框架结构震害总体较轻,未合理设计的楼梯及填充墙依然是框架结构中震害集中区;砌体结构墙体出现常见的各种斜向裂缝;除设计因素外,造成少量砌体结构倒塌可能原因是传统砌体结构抵抗竖向地震作用能力不足以及特殊场地地震放大效应。根据两种结构类型的建筑震害特征,对灾区重建及既有房屋改造提出了重点加强老旧建筑合规性排查、合理计算不利地段建筑的地震作用、适当引入合适的减隔震装置等针对性的设计建议,以提高城镇居住建筑的抗震能力,同时体现韧性城镇的设计理念。

To analyze the damage of urban residential buildings in Ms6.8 Luding earthquake,typical seismic damage to residential buildings in Moxi town and surrounding towns was investigated,seismic damage characteristics of frame structure and masonry structure in urban residential buildings were summarized,seismic damage of a high⁃rise residence with frame structure and a multi⁃story staff dormitory with masonry structure were introduced in detail,and the cause of the damage was analyzed.The results from the investigation and analyses show that in this earthquake,the damage of frame structure and masonry structure was generally more serious at the bottom.The overall seismic damage of frame structure was relatively light,and the stairs and infilled walls that were not reasonably designed were still the concentrated areas of seismic damage in the frame structure.All kinds of common oblique cracks appeared in masonry structure wall.In addition to the design factors,the possible reasons for the collapse of a small number of masonry structures were the insufficient resistance of traditional masonry structures to vertical seismic action and the seismic amplification effect of special sites.According to the seismic damage characteristics of buildings of two types of structures,targeted design suggestions were put forward for the reconstruction of disaster areas and the reconstruction of existing buildings,such as strengthening the compliance inspection of old buildings,reasonably calculating the seismic action of buildings in unfavorable sections,and properly introducing appropriate seismic reduction and isolation devices,to improve the seismic capacity of urban residential buildings,while reflecting the design concept of resilient cities.