江苏泗阳城区浅层粉土工程地质特性分析

根据研究区158个场地近千个浅层钻孔的试验成果,从沉积特性入手分析了研究区浅层粉土的成因类型与典型沉积组合剖面。通过室内试验成果的统计分析,研究了浅层粉土颗粒组成特征、化学矿物成份及其基本物理力学性质,同时,结合静探试验与荷载试验成果,分别建立了与主要物理力学性质指标的相关性经验方程。采用变水头试验与典型工程抽水试验、取土坑击实试验以及标准贯入试验分别对研究区浅层粉土的渗透性、击实性和振动液化性进行了分析,结果表明:研究区浅层粉土通过室内变水头试验与现场抽水试验得出的渗透性指标相差1~2个数量级,现场抽水试验更接近粉土的实际渗透性指标;研究区浅层粉土具有水稳定性差、不易压实的特点;研究区浅层粉土多为可液化土层,液化等级从轻微液化至严重液化,地域性特征明显。研究成果给泗阳城市规划建设提供了一定的借鉴作用,也为进一步深入研究本地区浅层粉土提供基础资料。

Analysis on Engineering Characteristics of Shallow Silt Soil in Siyang Area,Jiangsu Province

Base on the test results of a large of samples from 158 projects, genetic type and typical combination geological sections of shallow silt soils in Siyang Area, Jiangsu Province, were analyzed respectively in terms of the sedimentary characteristics. Components of particles and chemical mineral composition and basic mechanical properties of the shallow silt soils were analyzed with the statistical analysis of the test results, combined with the static test and load test results, the correlation equation and the main physical and mechanical properties were established. Using variable head permeability test and typical engineering pumping test, borrow pits compaction test and standard penetration test, Permeability, compaction and liquefaction were studied. Using laboratory head test and field pumping test results show that the permeability index difference of 1~2 orders of magnitude, the field pumping test index is closer to the actual penetration of shallow silt soils in the study area; the characteristics of shallow silt soils with bad water stability and not easy compaction; the liquefaction of the shallow silt soil occurred extensively in the study area, liquefaction grade from mild liquefaction to serious liquefaction, the regional characteristics of significant. The research results provide some good advice for the planning and construction of Siyang city, and also provide basic information for further research.