地下通道开挖对邻近条形基础的影响

运用理论分析和数值模拟相结合的方法研究了地下通道开挖引起地表沉降及对邻近条形基础的影响,并给出了条形基础竖直沉降和水平位移最敏感距离的估算方法。文章首先针对无条形基础的自由场地基运用三维快速拉格朗日差分软件FLAC3D进行数值模拟并与Peck推导的理论公式即Peck公式进行地表沉降的对比验证,证明该数值模型的可靠性。然后通过数值模拟,研究了距地下通道中心轴线不同距离的条形基础在地下通道开挖时的沉降和水平位移。最后,根据计算结果给出邻近条形基础的地下通道开挖的安全距离,为安全施工提供依据。

Responses of strip foundation caused by adjacent underpass excavating

Surface subsidence caused by underground excavation and its influence on adjacent strip foundation has been researched by theoretical analysis and numerical simulation,the estimation method of strip foundation vertical settlement and horizontal displacement of the most sensitive distance has been raised. In the paper,three-dimensional fast Lagrangian finite difference software FLAC3 Dhas been used to simulate and analyze the free field ground numerical example without strip foundation,then,comparing the result with the theoretical formula of surface subsidence derived by Peck to prove the reliability of the numerical model. The settlement and horizontal displacement of the strip foundation caused by underground tunnel excavation,from the different axial distance center of underground tunnel,was researched. At last,according to the calculation results of underground tunnel excavation,a safe distance has been given and the reference for safety construction is provided.