砂岩吸水特性试验

Experimental research on hydrophilic characteristics of sandstone in deep mine

为了研究砂岩吸水随时间的变化规律,利用深部软岩水理作用测试仪,对鹤岗南山矿深部和浅部砂岩进行了吸水试验,并通过粉晶X-射线衍射试验、压汞和SEM电镜扫描测试,分析了影响砂岩吸水特性的主要因素,建立了砂岩吸水过程函数。结果表明:无论是深部还是浅部砂岩,其吸水过程均具有时间效应,吸水速率随时间改变;吸水特征双对数曲线呈凸凹型和直线型。孔隙结构呈A类分形特征的砂岩,吸水速率变化较小,吸水特征双对数曲线多呈直线型,孔隙结构呈B、C类分形特征的砂岩,吸水速率变化较大,吸水特征双对数曲线多呈凹凸型。砂岩中矿物种类与含量、粒间孔隙中黏土矿物类型与产状均对吸水速率产生影响。

To better understand hydrophilic behaviors of sandstone in deep mine, a series of hydrophilic experiments on sandstone samples located at deep mine of Nanshan coal-mine at Hegang city of China were carried out with the help of the hydrophilic testing system in deep mine. Combining SEM technique with powder diffraction analysis of X-ray and pressure pump tests, main factors influering hydrophilic charac- teristics were studied and the hydrophilic process function of the sandstone were also obtained. The results show that the hydrophilic process of the sandstone in deep mine varies with time, that the hydrophilic relationship with time can be expressed by dual logarithm characterized by kinds of modes such as convex, concave and linear ones, that hydrophilic rate of the sandstone with A-type fractal microstructure changes slightly with time, and the dual logarithm function of hydrophilic process can be taken as linear, and that the hydrophilic rate of those with 13 and C-type fractal microstructure changes greatly and is always taken as concave-convex. It can be noted that the mineral ingredients and their content, porosities, and microstructures of clay minerals all have influence on soakage and hydrophilic rate for sandstone.