酸作用时间对页岩微观特征和力学性质的影响  

Effect of Acid Action Time on Microscopic and Mechanical Properties of Shale

作　　者：柳兵 党炜 聂毓斌 Bing Liu;Wei Deng;Yubin Nie(Sinohydro Engineering Bureau 4 Co.,Ltd.,Xining 810000,P.R.China)

机构地区：[1]中国水利水电第四工程局有限公司,西宁810000

出　　处：《地下空间与工程学报》2024年第2期480-487,共8页Chinese Journal of Underground Space and Engineering

基　　金：国家自然科学基金(52178395)。

摘　　要：为探究页岩性质随酸性溶液作用时间的演化规律,采用CT扫描、核磁共振技术和单轴压缩实验对不同时间(0~80 d)处理后页岩的孔隙特征和力学性质演化规律进行了表征和分析。结果表明:由于矿物的溶蚀作用,随着酸溶液浸泡时间的增加,页岩基质中逐渐形成新的细观裂缝并不断扩展,页岩的总孔、大孔和中孔孔隙度逐渐增加,而微孔孔隙度逐渐减少;分形维数随酸溶液浸泡时间的增加逐渐递增,页岩的孔隙结构越来越复杂;酸性水溶液下孔隙度增大增强了页岩的损伤变量,最终导致了页单轴压缩强度和弹性模量弱化。To explore the evolution of shale properties with the action time of acid solution,CT scanning,nuclear magnetic resonance technology and uniaxial compression experiment were carried out.The pore characteristics and mechanical properties evolution of shale after different treatment time(0~80 days)were characterized and analyzed.The results show that with the increase of immersion time of acid solution,new meso-fractures are gradually formed in the shale matrix and expand continuously,the total pore,macropore and mesopore porosity of shale increase gradually,while the micropore porosity decreases gradually.The fractal dimension increases gradually with the increase of acid immersion time,which means the pore structure of shale becomes more and more complex.The increase of porosity in acidic aqueous solution enhances the damage variable of shale,and finally leads to the weakening of uniaxial compressive strength and elastic modulus.

关 键 词：酸性溶液 微观结构 页岩 化学溶蚀 分形维数 

分 类 号：U45[建筑科学—桥梁与隧道工程]