深穿开挖影响的覆土变形规律研究

Study on the Deformation Law of Overburden Affected by Deep Excavation

城市地下工程的大量建设对周边覆土层势的稳定性势必产生不同程度的影响。以高精度探地雷达前期普查和多维度变形测量后期监测为研究手段,对某城市深穿开挖隧道周边覆土进行变形规律研究。雷达前期普查首先确定了2处监测区域中度疏松区A和轻微疏松区C;后期监测数据显示,A,C区域x轴向变形规律明显,均面向开挖隧道,为整体变形,变形量随深度的增加而减小。y轴向变形无固定方向,且为分层错动;A区域变形深度范围为地下0~4m,2处各方向变形值最大为0.5mm,在安全范围内证明了支护结构的有效性。

A large number of urban underground engineering construction will inevitably have different degrees of impact on the stability of the surrounding overburden potential.In this paper,the deformation law of the surrounding soil around a deep excavation tunnel in a city is studied by means of high-precision GPR preliminary survey and multi-dimensional deformation measurement later monitoring.In the early stage of the radar general survey,two monitoring areas,moderate loose area A and slight loose area C,were firstly determined.In the later stage,the monitoring data showed that the x-axial deformation law of areas a and C was obvious,both facing the excavation tunnel,which was the overall deformation,and the deformation decreased with the increase of depth.There is no fixed direction for y-axis deformation,and it is staggered movement in layers.The deformation depth in area a is 0~4 m underground,and the maximum deformation value in each direction of the two areas is 0.5 mm,which proves the effectiveness of the support structure in the safe range.