高渗压小水力梯度岩石渗透性测试

对低渗透岩石的渗透性测试一般采用瞬时压力脉冲法，但该方法不能真实模拟野外高孔隙水压力、小水力梯度的现场实际条件，而且试验存在较大误差。为此开发研制了一套新型高压渗透仪，在渗透出水端安装了管路过滤器、调速阀两种器械元件，可手动任意调控流量大小，而流量大小采用精确测量渗出水体积变化量表示。试验只要保证进水端水压不变，当调控的水流量与试样的渗流量达到平衡时，则会在出水端形成一个稳定的水压值。该套试验设备不但可对圆柱体试样进行渗透性、力学特性测试，而且还可以对方柱体试样进行渗透性测试，实现了对岩石实际所处应力、高孔隙水压力环境的真实模拟。实测检验理论技术可行，达到了满意的试验效果。

Rock permeability test under high pore water pressure and low hydraulic gradient

The transient pressure pulse permeability test method is often used for low permeability rocks test. But this method can not truly simulate the high pore water pressure and low hydraulic gradient geological environment; and the test result is not accurate, either. Therefore, we developed a new high pressure permeability testing machine. The sample seepage outlet water flow velocity can be manually controlled at will with pipe filter and speed control valve; and the seepage quantity can be assured by accurate measurement of the effusion water change quantity. When the inlet water pressure of the sample is sure stable, the controlled water flow velocity will be balance with the sample seepage velocity; and the stable water pressure in the seepage outlet can be formed. It can truly simulate the rock stress and high hydraulic gradient environment. Not only the cylinder but also the cubic sample permeability can be measured with this machine. It has been proved by the test that this method can be used.