砂岩强度及平均模量和纵波速度关系研究

Study on Relation Among Strength,Average Moduli and Longitudinal Wave Velocities for Sandstone

基于对赵固一矿二1煤层顶板中砂岩的超声波测试、常规单轴以及三轴压缩试验,研究顶板中砂岩纵波速度、强度和平均模量之间的关系,以及围压对试样强度和变形的影响关系.试验结果表明:由于中砂岩受成岩环境的不同,造成岩样内部的材料结构存在差异,同一钻孔取得的岩芯自上而下颗粒由细变粗;岩样纵波速度、平均模量和强度依次增大,但平均模量、纵波速度和强度都是试样的综合宏观表现,三者没有明确的力学关系;三轴压缩强度、平均模量与围压具有相关性,多个试样经不同围压试验结果联合回归得到的结果能够表征中砂岩的强度特征;试样的差异主要体现在砂岩内部尺度较小的裂隙、层理面的数量和方向,其数量和分布的不同必将引起试样的波速、平均模量和强度的差异.

Based on ultrasonic diction,uniaxial and pseudo-triaxial compression tests of cylinder specimen that spud in medium grain sandstone from coal roof,we study the relationship between longitudinal wave velocities,strength and average moduli,and the effect of confine pressure on strength and strain.The tests indicate that,because of different diagenetic environment,1) the inside structures of rock material is different;2) the stonecore obtained from the same drill hole becomes bigger from top to bottom;and 3) t...