地震后地下受损拱结构的抗爆炸能力研究

摘要

为了评估地下结构的地震后抗爆炸能力,以边墙高3.0m、半径3.0m的半圆拱结构为模拟对象,假定了7种裂缝可能出现的位置.采用网格划分软件TrueGrid构建网格模型,基于LS-DYNA数值模拟分析地下拱结构在1条裂缝、2条裂缝和3条裂缝条件下的抗爆炸能力.分析结果表明:1条裂缝存在的条件下,地下拱结构的抗爆炸能力平均下降50％以上,裂缝的位置对地下拱结构的抗爆炸能力有明显影响,底板与边墙连接处的裂缝影响最大,拱顶正中的竖向裂缝影响最小;多条裂缝条件下的抗爆炸能力与单一裂缝相比没有明显区别,其抗爆炸能力的大小与各条裂缝单独存在时的最小抗爆炸能力相等.%The evaluation of anti-blasting ability of underground structures has become a new research subject since earthquake can seriously damage the underground structures.A semicircular arch structure with radius of arch of 3.0 m and height of side wall of 3.0 m is simulated,and seven kinds of cracks at different locations are presumed.TrueGrid is used to construct a mesh model,and then the anti-blasting ability of underground arch structure is numerically simulated by LS-DYNA.The results show that the anti-blasting ability of underground arch structure with a crack is dropped by more than 50％.The antiblasting ability of underground arch structure is affected by the location of cracks.The cracks between floor and side wall have the greatest effects on its anti-blasting ability and the cracks in arch crown have the least effects on its anti-blasting ability.The anti-blasting ability of arch structure with multi-cracks is not obviously different to that of arch structure with a single crack,and the anti-blasting ability is equal to the least value of anti-blasting ability when the cracks exist singly.