参数空间变异性对基坑周围土体变形影响分析

Analysis on Effect of Space Variability of Parameters on Soil Deformation around the Deep Excavation

通过理论分析与数值模拟相结合的方法,主要对因土体参数的空间变异性及随机性对基坑周围土体的变形影响进行了分析,研究表明基坑周围土体的变形主要受到粘聚力单因素变化、粘聚力和内摩擦角双因素共同变化时的空间变异性与随机性影响,而内摩擦角单因素变化对其的影响较小;由于参数的空间变异性与随机性所影响的区域不同,基坑周围土体的变形也不相同,由此也可以反映出土体固有的结构性;因土体参数空间变异性与随机性,基坑周围土体上部多受影响,建议在工程施工过程中相对不考虑其变化特性的设计,应该增强上部的支护强度,以确保工程安全以及减少周围土体的地表沉降,研究成果对工程施工设计有一定的指导意义。

Combining theoretical analysis with numerical simulation, this paper analyzes the deformation of the soil body around deep excavation which is influenced by space variability and randomness of its parameters. The following conclusions can be drawn. Considering the change of cohesive force and the change of cohesive force together with internal friction angle, the deformation of the soil body around deep excavation is mainly influenced by space variability and randominess, but the internal friction angle has less influence. Because the region affected by space variability and randominess of parameters is different, the deformation of the soil body around deep excavation is also dif- ferent, which reflects the inherent structural property of the soil body. The upside part of soil body around deep excavation is mostly influenced by space variability and randominess of parameters, so the strengthening of upside part is advised during the project performance in order to insure the engineering safety and reduce surface subsidence of soil around the deep excavation. The conclusion has some meaning to the guiding performance and design of a project.