城市暗挖隧道爆破施工引起的地表振动效应是影响地表建(构)筑物安全的重要因素之一。基于数值模拟、实测数据验证和量纲分析方法对不同埋深隧道爆破地震波在邻近地表一定范围内的反射叠加规律和地表振动速度衰减规律进行研究。研究结果表明:城市暗挖隧道爆破产生的地震波在邻近地表一定范围内会出现反射叠加现象,其影响范围随隧道埋深的增加而增大,反射叠加强度随隧道埋深的增加而减弱;论文提出考虑埋深影响的地表振动速度衰减计算公式能更好地反映地表振动速度的衰减规律。研究结果可为地震效应研究和工程施工提供参考。
The ground vibration caused by blasting is one of the important safety elements in metro tunnel.The ground vibration caused by tunnel blasting in different depth is analyzed by numerical simulation methods.A conclusion was drawn that the stress wave produces reflection and superposition phenomenon.At the same time the attenuation law of vibration velocity is studied combined with dimensional analysis.The conclusions show that the blasting stress wave reflects and stacks when wave passes surface.With the increase of tunnel buried depth, the influence depth of reflected wave increases.The improved formula is deduced with method of dimensional analysis when considering the influence of buried depth.And the formula is verified that it better reflect the law of vibration velocity.