桂东南泥盆系莲花山组泥岩膨胀性研究OA北大核心CSTPCD

The swellability of mudstone has important influence on slope stability and other geotechnical engi-neering.Lianhuashan Formation of the Devonian is developed in Cenxi City,central of southeast Guangxi.It is mainly distributed in a small scale in the low hill area of the stripped and dissolved ridges and valleys geomor-phologic area.In order to find out the dilatability of the mudstone in this area,this study has carried out geolog-ical mapping,drilling,field test,laboratory geotechnical test and X-ray diffraction analysis to determine the macro-characteristics and physical and mechanical properties of the mudstone.The swelling property of mud-stone is studied by the comprehensive evaluation method of macroscopic preliminary judgment—physical and mechanical indexes quantitative initial judgment—Gaussian process quantitative detailed judgment.The physical and mechanical indexes are selected as effective montmorillonite content,<2 μm colloidal content,liquid lim-it,plastic index and total swelling and shrinkage ratio,and the quantitative criterion of swelling property is giv-en.The five indexes of mudstone in the study area are 22%-33%,20%-33%,46.8%-78.0%,24.1-42.9 and 1.3%-5.2%,respectively.It is concluded that the mudstone in the study area has moderate to strong swellability.