水岩相互作用下钙芒硝盐岩强度衰减机理  

Strength Attenuation Mechanism of the Interaction between Water and Glauberite Salt Rock

作　　者：郭永春 周其健 屈智辉 郑立宁 祝全兵[3] Guo Yongchun;Zhou Qijian;Qu Zhihui;Zheng Lining;Zhu Quanbing(School of Geoscience and Environmental Engineering,Southwest Jiaotong University,Chengdu 610031,P.R.China;China Couthwest Architectural Design And Research Investitute Corp.Ltd,Chengdu 610093,P.R.China;China Water Conservancy and Hydropower Seventh Engineering Bureau Corp.Ltd,Chengdu 610213,P.R.China)

机构地区：[1]西南交通大学地球科学与环境工程学院,成都610031 [2]中国建筑西南勘察设计研究院有限公司,成都610093 [3]中国水利水电第七工程局有限公司,成都610213

出　　处：《地下空间与工程学报》2021年第4期1045-1051,共7页Chinese Journal of Underground Space and Engineering

摘　　要：针对成都南郊普遍分布的白垩系灌口组钙芒硝盐岩的强度衰减现象,在总结浸泡40 d过程中钙芒硝盐岩参数变化规律的基础上,采用手标本鉴定、X射线衍射全岩定量分析、岩石薄片鉴定等方法深入研究了水岩相互作用下钙芒硝盐岩强度衰减机理。研究结果表明,钙芒硝盐岩中的矿物成分、结构构造、浸水时间等因素对盐岩强度衰减影响显著,钙芒硝盐岩破坏模式从脆性破坏过渡为塑性破坏。钙芒硝盐岩强度衰减机理在微观上主要表现在矿物成分的溶解、岩石结构溶蚀、结构连接弱化等方面;在宏观上表现为钙芒硝盐岩软化、崩解、强度低、变形大。钙芒硝盐岩结构劣化性能可以用软化系数、结构损伤系数等参数进行描述,随着浸泡时间的增加,钙芒硝盐岩软化系数逐渐降低,损伤系数逐渐增大。Aiming at the phenomenon of the strength attenuation of glauberite salt rock in Guankou formation of Cretaceous,which is widely distributed in the southern suburb of Chengdu,on the basis of summing up the parameters of glauberite salt rock during the 40-day soaking period,through the analysis of the attenuation law of rock strength,the strength attenuation mechanism of the interaction of water and glauberite salt rock was studied by means of hand specimen identification,X-ray diffraction whole rock quantitative analysis and rock slice identification. The results show that the mineral composition,structural structure and soaking time of glauberite salt rock have significant influence on the strength attenuation of salt rock. The prominent failure mode changes from brittle failure to plastic failure. The strength attenuation mechanism of glauberite salt rock is mainly manifested in the dissolution of mineral composition,dissolution of rock structure,weakening of structural connection,etc. On the macro level,the rock shows softening,disintegration,low strength and large deformation. The deterioration performance of rock structure can be described by softening coefficient,structural damage coefficient and other parameters. With the increase of immersion time, the softening coefficient of rock decreases gradually and the damage coefficient increases gradually.

关 键 词：钙芒硝盐岩 强度衰减机理 水岩作用 含盐地层 岩石结构 

分 类 号：TQ533[化学工程—煤化学工程]