水热作用下钙芒硝溶蚀特性与力学特性试验  

Experimental Study on Dissolution and Mechanical Properties of Glauberite Under Hydrothermal Condition

作　　者：王景坤 于艳梅[1,2] WANG Jingkun;YU Yanmei(College of Mining Engineering,Taiyuan University of Technology,Taiyuan,Shanxi 030024,China;Key Laboratory of In-situ Property-improving Mining of Ministry of Education,Taiyuan University of Technology,Taiyuan,Shanxi 030024,China)

机构地区：[1]太原理工大学矿业工程学院,山西太原030024 [2]太原理工大学原位改性采矿教育部重点实验室,山西太原030024

出　　处：《矿业研究与开发》2022年第8期29-34,共6页Mining Research and Development

基　　金：国家自然科学基金资助项目(51504158)。

摘　　要：为了研究钙芒硝盐岩在不同温度水溶作用下的溶蚀及力学特性弱化规律,采用自研的一种CT扫描过程中实时加载加温溶浸试验装置,进行了不同温度淡水溶浸下钙芒硝盐岩实时显微CT扫描与单轴压缩试验。对比分析钙芒硝在不同温度水溶下的细观结构与力学特性变化,得出钙芒硝在不同温度水溶下的溶蚀规律,揭示力学特性弱化机理。研究结果表明:钙芒硝完全溶解结晶后,孔隙率从0.96%~2.65%增加到16.60%~18.41%;钙芒硝盐岩的溶解结晶厚度随时间的变化遵循幂函数关系:δ_(t)=at^(b);淡水温度从20℃增加到35℃时,溶解速度提升较大,从35℃增加到80℃时,溶解速度平缓增加,从80℃增加到95℃时溶解速度增加剧烈;未溶解结晶区的截面积S与单轴压缩强度P之间存在线性关系,针对直径20 mm的试件,可以表示为:P=1.767+0.0229S。研究成果对盐类矿床水溶开采、盐穴储气库建设以及其他有钙芒硝溶蚀问题的工程岩体稳定性研究有一定的指导意义。In order to study the dissolution and weakening law of mechanical properties of glauberite salt rock under water dissolution at different temperatures,a self-developed real-time loading and heating solution leaching test device during CT scanning was used to conduct real-time microscopic CT scanning and uniaxial compression test of glauberite salt rock under freshwater solution leaching at different temperatures.By comparing and analyzing the changes of meso-structure and mechanical properties of glauberite,the dissolution laws of glauberite dissolved in water at different temperatures were obtained,and the weakening mechanism of mechanical properties was revealed.The conclusions are obtained as follows.Firstly,the porosity of glauberite increases from 0.96%-2.65%to 16.60%-18.41%after completing dissolution and crystallization.Secondly,the change of dissolved crystallization thickness of glauberite salt rock with time follows a power function,which can be expressed as:δ_(t)=at^(b).Thirdly,when the fresh water temperature increases from 20℃to 35℃,the dissolution rate increases greatly,when the temperature increases from 35℃to 80℃,the dissolution rate increases gently,and when the temperature increases from 80℃to 95℃,the dissolution rate increases sharply.Finally,there is a linear relationship between the cross-sectional area S of the undissolved crystalline area and the uniaxial compressive strength P.For the specimen with a diameter of 20 mm,the formula can be expressed as P=1.767+0.0229S.The research results have a certain guiding significance for the water-soluble mining of salt deposits,the construction of salt cavern gas storage and the engineering rock mass stability study on dissolution problems in other calcium-containing mirabilite projects.

关 键 词：钙芒硝 淡水溶浸 实时CT扫描 温度时间效应 力学特性 

分 类 号：TD871[矿业工程—非金属矿开采] TD315[矿业工程—矿山开采]