高液限花岗岩残积土路用特性试验研究  

Experimental study on road characteristics of granite residual soil with high liquid limit

作　　者：刘冀 邓超[2] 胡焕校[2] 陈威 LIU Ji;DENG Chao;HU Huanxiao;CHEN Wei(Hunan Geology Exploration Institute of China Chemical Geology and Mine Bureau,Changsha 410100,China;School of Geosciences and Info-physics,Central South University,Changsha 410083,China)

机构地区：[1]中化地质矿山总局湖南地质勘查院,湖南长沙410100 [2]中南大学地球科学与信息物理学院,湖南长沙410083

出　　处：《水资源与水工程学报》2021年第2期194-201,共8页Journal of Water Resources and Water Engineering

基　　金：国家自然科学基金项目(52078494);中南大学中央高校基本科研业务费专项资金项目(2017zzts178)。

摘　　要：取湖南某高速公路路基土样进行室内试验,研究花岗岩残积类高液限土的路用特性。通过XRF荧光光谱、XRD粉晶衍射和薄片鉴定实验,分析该类高液限土的成分及结构,发现细粒片状云母等矿物与细粒状的黏土矿物相互作用是其特殊性质的主因。研究击实功、含水率对高液限花岗岩残积土的击实指标、压实度、CBR强度的影响规律,并探究泡水4 d后土样状态参数的变化。结果表明:中、低含水率分别与大、小击实功组合,该类土更密实,适合直接填筑;击实功影响下的CBR曲线峰值变化与击实曲线相反;对比泡水4 d前后CBR强度变化,建立该类土CBR强度损失率与泡水前含水率的关系,为高液限花岗岩残积土工程应用提供借鉴。In order to study road characteristics of high liquid limit soil of granite residual,the subgrade soil samples of an expressway in Hunan Province were taken for laboratory tests.Through XRF,XRD and thin section experiments,the mineral composition and basic structure of the soil samples were analyzed.It is found that the interaction between fine-grained/flaky mica and fine-grained clay contribute mostly to the specific properties of this soil.The effects of compaction energy and water content on the compaction index,compaction degree and CBR strength of the granite residual soil were studied and the change of state parameters of the soil samples which have been submerged in water for four days were analyzed.The results reveal that in order to get denser soil for the direct application to subgrade filling,the medium and low water contents have to be matched with large and small compaction energy respectively.The variation of peak values of CBR curve under different compaction energy is contrary to the compaction curve.Furthermore,the relationship between loss rate of CBR strength and water content before the submersion was established based on the comparison and analysis of the changes of its CBR strength before and after four-day submersion in water.This study can provide some reference for the engineering application of high liquid limit granite residual soil.

关 键 词：高液限土 花岗岩残积土 室内试验 细观结构 CBR强度 路用特性 

分 类 号：TV223.1[水利工程—水工结构工程] TU45[建筑科学—岩土工程]