电化学作用下煤系泥岩孔隙和强度变化的试验研究

基于水溶液为纯净水和1 mol/L NaCl煤系泥岩的电化学改性对比试验,结合岩样的液氮吸附、单轴压缩和扫描电镜能谱分析结果,研究了电化学作用下泥岩孔隙和力学强度的变化规律。研究结果表明:电极及导线的电化学腐蚀主要发生在阳极,且水溶液为1 mol/L NaCl时的腐蚀程度强于纯净水;相比自然样,电化学作用后岩样阴阳极区域比表面积累积和孔容累积均不同程度的降低,比表面积累积阴极区域降低幅度明显大于阳极,而孔容累积阴极区域降低幅度小于阳极;水溶液为1 mol/L NaCl岩样阴阳极区域孔隙比表面积、孔容均小于水溶液为纯净水时;电化学作用后岩样的单轴抗压强度、弹性模量和变形模量均显著增强,水溶液为1 mol/L NaCl时岩样的增强程度高于水溶液为纯净水时。

Experimental study on pore and strength change of mudstone from the coal measure strata under electro-chemical

Based on the electro-chemical modification comparison test of mudstone from the coal measure strata under aqueous solution in purified water and 1 mol/L NaCl water solution and by combining the results of liquid nitrogen adsorption,uniaxial compression test and scanning electron microscopy energy dispersive spectrum (SEM-EDS),the change rules of pore and strength of mudstone for different zone under electro-chemical were studied.Following results have been gotten:The electro-chemical corrosion of electrode and wire occurred mainly in anodic zone,and the corrosion degree of anodic electrode in 1 mol/L NaCl water solution is significantly heavier than in purified water.After electro-chemical modification,the accumulated surface area and pore volume of samples from anodic and cathodic zone decrease with different degrees when compared with the samples in the state of nature,and the declined level of the accumulated surface area of samples from cathodic zone is heavier than that from anodic zone,while the decreased rating of the accumulated pore volume of samples from cathodic zone is less than from anodic zone.The accumulated surface area and pore volume of samples from anodic and cathodic zone with 1 mol/L NaCl water solution were larger than that with purified water.The uniaxial compressive strength (UCS),elastic modulus (E) and deformation modulus (Ed) of the electrochemical modified samples is significantly higher than that of the unmodified samples,and the strength of samples in 1 mol/L NaCl water solution is higher than that in purified water.