岩溶红土地基中的软土类型及其工程特性

根据岩溶红土地基软土的形成条件划分出了岩沟型、层间型及洞中型三种不同的软土类型,在此基础上,通过取样测试并结合前人已有成果,对不同类型软土的工程地质特性进行了分析。研究结果表明:(1)岩溶红土地基软土是一种与岩溶作用关系密切的特殊软土;(2)岩溶红土地基软土的天然含水量和压缩性均明显小而重度又普遍高于泻湖相软土;(3)60%的岩沟型残积软土其天然含水量均小于液限含水量;(4)岩溶红土地基软土的工程地质问题主要表现为地基不均匀沉陷、边坡失稳和诱发土洞塌陷等。基于岩溶红土地基软土形成条件及其工程地质性质比较特殊,建议把它叫作"岩溶软土",以示与其它成因软土相区别。

Types of soft soil in karst laterite and its engineering properties

Three types of soft soil in karst laterite,i.e.rocky clint type,intrastratal type and earth cave or earth pit type are divided based on their formative conditions,and the engineering properties of different types of the soft soil are analysed together with the data investigated and tested by the author himself and others in this paper.The results show that:(1) each kind of soft soil above is a special soil closely related to karstification;(2) the natural water content and compressibility of the soft soil in karst laterite are less than that of the lagoon soft,while the natural unit weight is higher;(3) about 60% of the natural water contents are smaller than the liquid limit water contents for the samples taken from the eluvial soft soil in rocky clint;(4) the main engineering geological problems of soft soil in karst laterite are uneven subsidence of foundation soil,slip of mountain slope and earth cave and collapse caused by groundwater.As the soft soil in karst laterite has a lot of special properties,a suggestion that the soft soil in karst laterite should be called "karst soft soil" is put forward in the paper.