泥质岩膨胀各向异性与循环胀缩特征  

Swelling anisotropy and cyclic swelling-shrinkage of argillaceous rock

作　　者：柴肇云[1] 张鹏[1] 郭俊庆[1] 康天合[1] 

机构地区：[1]太原理工大学采矿工艺研究所,太原030024

出　　处：《岩土力学》2014年第2期346-350,440,共6页Rock and Soil Mechanics

基　　金：国家自然科学基金资助项目(No.51004075);山西省青年科技研究基金项目(No.2011021024-2);山西省高校优秀青年学术带头人计划项目(No.2012);太原理工大学校青年团队启动项目(No.2013T008)

摘　　要：采用自主开发研制的软岩膨胀试验装置,对新生代煤系地层中泥质岩进行膨胀试验研究,分析了泥质岩膨胀各向异性以及循环胀缩特性,并结合SEM试验结果,探讨了膨胀各向异性和循环胀缩特性的形成机制。结果表明:泥质岩膨胀性随岩样端面与层理面夹角的增大而减小,具有明显的各向异性;泥质岩所含黏土矿物颗粒排列的择优取向导致了泥质岩吸水膨胀的各向异性,可通过膨胀各向异性系数进行定量描述;随着干湿循环次数的增加,泥质岩绝对膨胀率增加,趋于某一稳定值;相对膨胀率和相对收缩率降低,亦趋于某一稳定值;泥质岩循环胀缩特性是干湿循环过程中矿物颗粒排列方式改变和微裂隙萌生扩展的能量耗散共同作用的结果。In order to grasp the swelling characteristics of argillaceous rock from coal measure strata in Cenozoic era, a self-developed soft rock swelling experiment apparatus is used to analyze swelling anisotropy and cyclic swelling-shrinkage. The essential mechanisms of swelling anisotropy and cyclic swelling-shrinkage of argillaceous rock are discussed by using scanning electron microscope （SEM）. Results show that the swelling of argillaceous rock decreases with an increase angle between the horizontal plane of device and bedding plane of specimen, and has obvious anisotropy. The anisotropy property of argillaceous rock swelling with water is caused by the preferred orientation of clay mineral particles arrangement, and it can be quantitative described by swelling anisotropy coefficient. With the increase of wetting-drying cycles, absolute swelling ratio increases and tends to be stable, but relative swelling and relative shrinkage ratios decrease and stabilize. Cyclic swelling-shrinkage of argillaceous rock is the outcome of combined effect, which is alter of arrangement of mineral particles and energy dissipation during the occurrence and development of micro-cracks.

关 键 词：泥岩 干湿循环 胀缩性 膨胀各向异性 绝对膨胀 相对膨胀 

分 类 号：TU451[建筑科学—岩土工程]