为了研究隧道爆破开挖条件下地表建筑的振动速度响应规律,以福州高速公路魁岐1号隧道工程为例,对隧道上部地表建筑进行振动速度监测,同时结合隧道现场的实际施工情况,利用ANSYS/LS-DYNA动力有限元分析软件对隧道爆破开挖引起的地表建筑的振动速度响应进行了数值模拟。通过分析现场实测和数值模拟结果得出以下结论:对比不同爆源条件下,地表建筑测点的峰值振动速度随爆源距的增大而减小,而在相同爆源条件下,地表建筑测点的峰值振动速度随爆源距的增大呈现先减小而后迅速增大的现象;地表建筑测点的峰值振动速度随测点高度的增大有明显的放大效应,且测点高度越大,放大效应越明显;隧道开挖成型后的空洞对于地表建筑测点的峰值振动速度具有明显的空洞放大效应,且空洞距离建筑越近,放大效应越明显;考虑建筑测点峰值振动速度的空洞放大效应时,隧道开挖宜采用先开挖深埋硐室后开挖浅埋硐室的施工顺序。
In order to research the vibration velocity responses of surface building under the condition of blasting excavation in tunnel, the vibration velocity of surface building was monitored by taking Kui-qi 1# highway tunnel in Fuzhou city as an example. Meanwhile, with the actual construction of tunnel, the vibration velocity responses of the surface building under the condition of blasting excavation in tunnel were studied by use of the ANSYS/LS-DYNA dynamical finite-element program. The analysis of field measurement and numerical simulation results shows that: (a) Comparing the different explosive sources, the peak vibration velocities of measuring points in the surface building decrease with the increase of distance to explosive source. The peak vibration velocities of measuring points in the surface building decrease firstly and then highly increase with the increase of distance to explosive source for the same explosive sources; (b) The peak vibration velocities of measuring points in the surface building increase with the increase of the height of measuring points, the higher the measuring points, the more obvious the amplification effect; (c) The peak vibration velocities of measuring points in the surface building have obvious empty amplification, the smaller the distance between building and empty, the more obvious the amplification effect; (d) Considering the peak vibration velocity empty amplification effect of the surface building measuring points, the deeply buried cavern should be excavated before the shallow cavern.