基于原位试验的软土地基安全性参数的研究

为了提高软土地基工程的安全性,合理确定软土地基安全性参数的取值,对天津滨海新区的一处软土地基进行平板载荷试验和预钻式旁压试验,分析了软土地基承载力和变形参数的空间特征。结果显示,由载荷试验得到的软土竖直向地基承载力和变形模量,在水平位置上的分布虽然各不相同,但差距并不大;采用预钻旁压仪得到的水平向地基承载力和变形模量与深度呈明显的线性关系;基于表层的地基承载力和变形模量值提出了各向异性指标,并由各向异性指标提出了采用预钻旁压实测值确定不同深度处竖直向地基承载力和变形模量的方法。

Research on Bearing Capacity and Deformation Characteristics of Soft Soil Foundation Based on In-situ Test

In order to improve the safety of soil foundation engineering and reasonably determine the value of the safety parameters of soft soil foundation,the flat plate load test and pre-drilling side pressure test were carried out on a soft soil foundation in Binhai new area of Tianjin,and the spatial characteristics of the bearing capacity and deformation parameters of soft soil foundation were analyzed.The results show that the vertical bearing capacities and deformation modulus of soft soil obtained by flat loading tests are different from each other on the surface of the foundation but the difference are not large.There is a clear linear relationship between horizontal bearing capacity and deformation modulus from pressure meter tests with the depth.Anisotropy index is proposed based on bearing capacity and deformation modulus value in the surface layer.Finally,a method for determining the bearing capacity and deformation modulus of vertical foundations at different depths by using pressure meter is proposed from the anisotropy index.