溶解应力耦合作用下钙芒硝的细观结构演化特征  

Microstructural Development of Glauberite Under Coupling Effect of Solution and Stress

作　　者：李健[1,2] 于艳梅[1,2] 卢玉玺[1,2] LI Jian;YU Yanmei;LU Yuxi(Department 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》2020年第5期23-26,共4页Mining Research and Development

基　　金：国家自然科学基金资助项目(51504158)

摘　　要：矿物溶解是一个多因素耦合作用下的复杂物理化学过程。为了研究钙芒硝细观结构演化规律,选用常温淡水溶浸后的钙芒硝,对其进行不同轴向应力作用下的试验研究。通过显微CT扫描观测和孔裂隙统计分析,结果表明:钙芒硝在淡水中溶浸后,孔隙总数量随轴向应力的增大先增加后减少。随着轴向应力的增加,等效直径<0.05mm的原生孔隙逐渐减少,0.05~0.5 mm的孔隙逐渐增多,当应力为8MPa时出现了>0.5mm的裂隙,9.6 MPa时出现了明显的裂隙。钙芒硝经淡水溶浸作用后,力学特性弱化,抗压强度大幅降低。轴向应力升高加剧钙芒硝孔裂隙的发生发展,提高矿体所受应力有助于钙芒硝溶解通道的形成。Mineral dissolution is a complex physicochemical process under the coupling effect of many factors.In order to study the microstructural evolution of glauberite,the glauberite dissolved in fresh water at room temperature was selected and tested under different axial stresses.Through micro-CT scanning observation and pores statistical analysis,the results showed that the total number of pores increased firstly and then decreased with the increase of axial stress after the dissolution of glauberite in fresh water.With the increase of the axial stress,the primary pores with the equivalent diameter less than 0.05 mm gradually decreased,and the pores with the equivalent diameter in 0.05~0.5 mm gradually increased.When the stress was 8 MPa,cracks with the equivalent diameter more than 0.5 mm appeared,and when the stress was 9.6 MPa,cracks became obvious.The mechanical properties of glauberite were weakened and the compressive strength was greatly reduced,after the dissolution in fresh water.The increase of axial stress intensified the occurrence and development of glauberite pores and cracks,so increasing the stress on ore body was conductive to the formation of glauberite dissolution channel.

关 键 词：钙芒硝 溶浸采矿 孔隙率 细观结构 等效直径 

分 类 号：TD315[矿业工程—矿井建设]