地下室对邻近地表和地下结构地震响应的影响

Influence analysis of basement on structure seismic response

为确定土结构相互作用影响程度以及地下室对地表结构、地下结构和场地土响应的影响,构建了自由场、地下结构-土-不带地下室地表结构以及地下结构-土-带地下室地表结构3个模型,计算其在不同地震动作用下的地震响应规律。对比分析表明:1)地表结构的存在导致周围土表响应增大,影响范围超过7倍的结构基础宽度,且相比于无地下室的情况,有地下室存在时增大程度更为明显;2)输入地震动较小时,无地下室地表结构的加速度和层间相对位移响应分别比有地下室地表结构大8%和20%,而输入地震动较大时,地下室的影响规律并不明显;3)输入地震动较小时,地下室的存在对邻近地下结构变形的影响较小,而输入地震动较大时,地下室的存在导致临近地下结构层间位移角增大。因此,在实际工程中应考虑地下室对地表结构与地下结构地震响应的影响。

In order to determine the influence of soil-structure interaction and the basement on surface structure,underground structure and soil seismic response,three calculation models of free-field,underground structure-soil-surface structure with basement and underground structure-soil-surface structure without basement were established.The seismic responses of the three models were calculated and analyzed under different ground motions.The results show that:(1)The existence of the surface structure leads to an increase in the response of the surrounding soil,and the impact range exceeds 7 times width of the structural foundation.Compared with the case without basement,the amplification is obvious when there is a basement.(2)When the amplitude of input wave is small,the acceleration and inter-story relative displacement of the surface structure without basement are 8%and 20%larger than that of the surface structure with basement,respectively.When the amplitude of input wave is big,the influence of the basement is not obvious.(3)When the amplitude of input wave is small,the existence of the basement has little influence on the deformation of the adjacent underground structure.When the amplitude of input wave is big,the existence of the basement will increase the inter-story drift angle of the adjacent underground structures.Therefore,the influence of basement on seismic response of adjacent surface structure and underground structure should be considered in practical engineering.