针对良志嘉年华二期项目,基于地下水渗流的基本规律和土体受力的本构模型,建立了渗流场与应力场耦合下的有限元模型,通过PLAXIS有限元软件进行了数值模拟分析,对考虑降水作用和未考虑地下水作用影响的两种情况下,复合土钉柔性支挡结构体系的位移进行探讨,为保证分析的精度,模型采用15节点三角形单元.分析结果表明:在考虑了降水作用时,基坑的总位移不仅包括滑动面内土体的位移,还包括坑后由于降水引起的位移。在降水作用下,引起支护结构的水平位移比竖向位移大,且引起的竖向位移能有效地减小基坑底面的隆起量。并且土质状况对支护结构体系位移的影响也很大。
According to the phase 2 engineering of Liangzhi Jianianhua project, based on the basic rules of groundwater seepage and the constitutive model of soil mass, the finite element model is established which considers the coupling-model of seepage and stress. In the case of considering dewatering and non- groundwater, the displacement of the composite soil nailing structure is simulated and analyzed by using software PLAXIS for finite element numerical computation. In order to ensure the calculation precision, the triangle elements with 15 nodes are used in the model. The analyzing results show that: In the case of considering dewatering, the total displacement of foundation pit contain not only the displacement in the sliding surface soil but also the soil displacement behind the pit; In the effect of the dewatering, the horizontal displacement of the supporting structure is larger than the vertical displacement, and the vertical displacement caused by the dewatering could effectively reduced the amount of the foundation pit uplift; The soil conditions are of the great impact on the displacement of the supporting structure system.