复合地层下TBM施工既有建筑物数值模拟研究

Numerical simulation of existing buildings constructed by TBM under composite stratum

在城市中的开挖隧道,如果是在硬岩中开挖,最好的施工方法为TBM法施工。但是在施工过程中同样地会遇到一些问题,如施工振动、噪音和对岩体的原有平衡的破坏,都是会对周围环境产生影响。以某隧道TBM施工为背景,研究了在复合地层下TBM隧道开挖对既有建筑物的影响研究,主要得出以下结论:(1)随着既有建筑物的高度增加,建筑物的最大沉降越大,越上部的楼板沉降越大,隧道穿越处的建筑物中线较两侧沉降较大,这说明建筑物楼板会有不均匀沉降,下穿施工可能会导致建筑物裂缝的产生;(2)建筑物剪应力较大的部位为柱下部区域,最大剪应力值出现在地层柱的柱下部。对于层数越高的建筑物,在施工中应加强对建筑物底层柱的应力监测。

When excavating tunnels in cities and in hard rock,the best construction method is TBM method.However,some problems will also be encountered in the construction process,such as construction vibration,noise and damage to the original balance of rock mass,which will have an impact on the surrounding environment.Based on the TBM construction of a tunnel,this paper studies the impact of TBM tunnel excavation on existing buildings in composite stratum.The main conclusions are as follows:(1) with the increase of the height of existing buildings,the greater the maximum settlement of buildings,the greater the floor settlement of the upper part.The settlement of the central line of the building at the tunnel crossing is larger than that on both sides,which indicates that the floor slab of the building will have uneven settlement,and the underpass construction may lead to the generation of building cracks;(2) The part with large shear stress of the building is the lower part of the column,and the maximum shear stress appears in the lower part of the formation column.For buildings with higher floors,the stress monitoring of the bottom column of the building should be strengthened during construction.