隧道埋深对地铁运行诱发振动的影响分析

采用FLAC^30建立了三维弹塑性动力有限差分模型，综合考虑衬砌、地层和地表的动力相互效应，就珠三角软土地层隧道埋深对地铁运行诱发相关振动的影响规律进行了分析。结果表明，隧道埋深对地铁运行诱发的衬砌环、周围地层和地表的动力响应产生了明显的影响，埋深越浅则动力响应越强，埋深越大则动力响应越弱。埋深对衬砌环的影响主要表现为使其发生不同的整体下沉响应；埋深不仅影响到地层动力响应强度，还影响到其受振范围；适当增大隧道埋深有助于减小地表噪声和振感。计算值与实测值吻合良好。

Influence of Tunnel Burial Depth on Dynamic Response Induced by Metro Operation

The elastoplastic 3D dynamic finite difference model was established by using FLAC3D numerical software. By fully con- sidering the inter-effect of the lining, the stratum and the ground, the influence of burial depth of tunnel on correlative dynamic response induced by metro operation was numerically simulated. The results show that, burial depth of tunnel induces significant influence on dynamic response of the lining, the stratum and the ground. The shallower the burial depth is, the severer the dynamic re- sponse is, and vice versa. For the lining-ring, different burial depth mainly results in different whole displacement response. For the stratum, the burial depth affects not only the intensity of dynamic response but also the range of affected region. It is a good way to reduce the noise and vibration on the ground by augmenting the burial depth of tunnel. The simulation results are conformed favorably with the site test.