地下结构抗震性能及指标体系研究综述

A review of research on seismic performance and index system of underground structures

地下结构是城市中重要的生命线工程,其抗震问题日益突出。现有研究对地下结构在地震中力学行为和破坏模式的认识越来越深入,关于地下结构抗震性能及指标体系的讨论越来越多。本文从地下结构地震破坏机理、地下结构性能水准划分、地下结构抗震性能指标三个方面,对近年来关于地下结构抗震性能及指标体系的研究成果进行梳理。总体上,地下结构在地震中的动力反应机理与地上结构存在明显不同,一般认为地铁地下结构中柱抗震性能不足是导致结构倒塌的重要因素;地下结构破坏后修复困难,应采取比地面建筑物更为严格的抗震设防目标;地铁车站结构的抗震性能多以层间位移角为评价指标,但现有规范及研究成果对各性能水准对应指标限值的结论相差比较大。

As an important lifeline project in cities, the earthquake resistance problem of underground structure is increasingly prominent. Existing researches have deepened the understanding of the mechanical behavior and failure mechanism of underground structures during earthquakes, and there have been increasingly discussions on the seismic performance and index system of underground structures. In this paper, the recent research on seismic damage mechanism and performance index system of underground structures are summarized from three aspects of earthquake failure mechanism, performance level division, and seismic performance index. In general, the dynamic response of underground structures is obviously different from that of above-ground structures. It is generally believed that the damage of structural columns is a significant factor leading to the structure collapse. Once the underground structure damaged, the repair is difficult;it is necessary to adopt more strict anti-seismic fortification target than the ground building. The seismic performance of subway station structure is mainly evaluated by the inter-story drift. However, the conclusions of the existing codes and research results on the limit value of the performance index are quite different.