【作者】 曾召田； 赵艳林； 吕海波； 尹国强； 徐云山；

【Author】 ZENG Zhaotian;ZHAO Yanlin;LU Haibo;YIN Guoqiang;XU Yunshan;Guangxi Key Laboratory of New Energy and Building Energy Saving(Guilin University of Technology);College of Civil Engineering,Guangxi University;

【机构】 广西建筑新能源与节能重点实验室(桂林理工大学)； 广西大学土木建筑工程学院；

【摘要】 红黏土的地质成因是其特殊工程性质的根本来源。本文在剖析广西岩溶地貌特征和红黏土形成、分布特点的基础上,着重选择广西岩溶地区的4种红黏土作为研究对象,通过现场采样、剖面特征描述、室内土工试验、微观实验等手段,对广西红黏土的工程地质特征及成因进行了深入分析,为揭示红黏土特殊的物理化学特性及工程应用提供依据。研究结果表明:(1)广西典型的湿热气候、广泛发育的岩溶环境有利于红黏土的形成;(2)广西红黏土具有一般红黏土的特性,矿物成分以高亲水性的高岭石、伊利石、蒙脱石为主,微观上呈现粒团内孔隙和粒团间孔隙并存的"二级"孔隙结构;(3)广西地区红黏土的地质剖面表现出明显的分层现象,从地表开始至碳酸盐基岩面,随着深度的递增,红黏土的孔隙比、含水率、液限、塑性指数、自由膨胀率和收缩性均呈现出逐渐增大的趋势,而其密度、干密度等指标却与之相反,呈现出逐渐变小的趋势;(4)从地质成因来看,桂林、柳州、武鸣三地均属于残积、残坡积红黏土,而来宾则属于冲洪积红黏土。更多还原

【Abstract】 The geological genesis of red clay is the fundamental source of its special engineering characteristics.Based on analysis of Guangxi karst landscapes and distribution characteristics of the red clay,this paper chose 4kinds of red clay in Guangxi karst area as the research objects to make an in-depth analysis of the engineering geological characteristics and genesis of red clay in karst area of Guangxi by field sampling,profile feature description,laboratory soil test and microscopic experiment.The research shows that:(1) The typical hot-humid climate and well-developed karst environment in Guangxi are beneficial to the formation of red clay.(2) Guangxi red clay has the general characteristics of red clay,such as the mineral component with kaolinte,illite,montmorillonite and the "double" pore structure with aggregate in the micro pore and particle mass pore.(3) It is the characteristics of Guangxi red clay from the surface to the bed rock that void ration,water content liquid limit,plasticity index,free swell and shrinkage increase gradually,while the density and dry density becomes smaller,and it shows obvious stratification.(4)Considering the geological genesis,the red clays from Guilin,Liuzhou and Wuming are residual red clays,and Laibin red clay is an alluvial red clay.更多还原