沉积岩矿物组成对其耐崩解性影响的试验研究

摘要

为了研究沉积岩耐崩解性差异及差异产生机理与矿物组成的关系,以阜新矿区煤炭开采所排出的煤矸石中几种典型的沉积岩(粗砾砂岩、细砾砂岩、粉砂岩、泥岩)为研究对象,通过X射线衍射(XRD)、X射线荧光光谱分析(XRF)及压汞试验(MIP)对岩石试样的矿物成分、化学成分和孔隙率进行测试分析,并利用耐崩解试验来定量化表征岩石的崩解特性,分析了岩石矿物组成对崩解特性的影响,并探讨了崩解性差异产生的机理.研究结果表明:沉积岩的耐崩解性与其矿物组成、化学组成和孔隙率有密切关系;随着耐崩解循环次数的增加,沉积岩的耐崩解指数会逐渐降低;沉积岩的崩解机理可以分为2类:矿物成分中伊利石含量较高的(大于10％),崩解主要由所含黏土矿物遇水引发试样的差异膨胀造成;矿物成分中伊利石含量较低的(小于10％),崩解主要由试样中化学成分遇水电离和孔隙遇水扩容造成.%In order to study the difference of sedimentary rock slake durability,its mechanism and its relationship with mineral composion,this article set several representative types of sedimentary rock (such as coarse gravel sandstone,fine gravel sandstone,siltstone,and mudstone) as a study example in Fuxin Mining Area,by using XRD,XRF and MIP to test and analyze rock samples mineral composition,element component as well as porosity.It also utilized the resistant to disintegration test to quantify the charaeterization of rock disintegration characteristics,and analyzed the influence which might cause by rock mineral composition and discussed the disintegration of difference.The results showed that the disintegration resistance of sedimentary rocks was closely related to mineral composition,element composition and porosity.With the increase of durable disintegration test cycles,sedimentary rock collapse resistance index would decrease gradually.The slaking of the sedimentary rock could be divided into two types:the content of illite which in mineral composition was higher (over 10％),the rock slaking was resulted from block swelling difference caused by clay minerals expansion in water.The content of illite which in mineral composition was lower (under 10％),the rock slaking was resulted from the element in the sample ionized with water and pore water expansion.