人造砂岩制作方法及其声学性质研究

Methods of making artificial sandstone and its acoustic properties

人造砂岩具有参数可控特点,可广泛的应用于物理模拟及实验研究领域.文章介绍了压制法制作人造砂岩的基本流程.对人造砂岩物理参数及声学性质进行实验研究.测量了密度、孔隙度等参数,给出压制压力与密度、纵波速度关系图.利用超声波透射法测量人造砂岩纵横波速度,对人工砂岩在饱含气与饱含水状态下速度变化进行定量分析,给出纵横波速度随孔隙度变化曲线.饱含气状态变化到饱含水状态后,纵波速度上升,横波速度下降.利用Gassmann方程对流体替换后速度进行预测,实际测试数据的纵波速度与预测计算数据比较吻合.纵横波速度变化规律与天然砂岩基本一致.

The properties of artificial sandstone are similar to natural sandstone, thus can be widely applied to physical simulation and experimental research field. This paper introduces a method of making artificial sandstone, and measure the density and porosity of sandstone. The pressure in manufacturing process is the key element to control the porosity and velocity of artificial sandstones. When the pressure increases, the porosity will decease, on the contrary the velocity will increase. The particle size of quartz sands and proportion of different materials are important parameters that determine physical properties of artificial sandstones. P-wave and s-wave velocities are measured by ultrasonic transmission method. Research the law of velocity variation when the sandstone pore is full of gas and water; establish relationship between p-wave velocity and porosity. When the pore fluid is replaced from gas to water, p-wave velocity increases and s-wave velocity decreases. Use Gassmann equation to predict the velocity of sandstone, the measured data are consistent with the calculated data.