岩石高压渗透试验装置的研制与开发

DEVELOPMENT AND RESEARCH OF HIGH PRESSURE PERMEABILITY TESTING SYSTEM FOR ROCKS

为提高对低渗透岩的测试精度,缩短渗透性测试时间,研究岩石(体)高孔隙水压力条件下的渗透、力学特性及其破坏机制,开发研制一套岩石高压渗透试验装置。该套装置可针对大尺寸,不同规格(圆柱体或方柱体)岩石(体)或碎石土还原在其原始地应力状态下进行渗透性及相关力学试验研究。围压、渗透压最大可加到30 MPa,轴向荷载最大可加到4 000 kN。试验通过精确度量渗出水体积的变化进行流量测定,大大提高了测试精度、缩短了测试时间。试样进水端水压以静态伺服阀为主要控制元件,可在脱离计算机控制条件下保持某一稳定水压值不变。在试样出水端采用管路过滤器、调速阀等组件对水流速度大小进行调控,当调节的流速与通过试样的渗透速度达到平衡时,即可在出水端产生某一稳定的水压值,进而在试样两端建立稳定的水压差。计算机调控灵活,具有可视化,可根据实际情况随时调整试验方案,而且操作命令语句可任意加长以满足试验要求。该试验装置解决了高孔隙水压、小水力梯度条件下的各种渗透性、高渗压下力学性质试验研究技术难关,这将为水电工程、石油、核电等领域相关试验研究提供新的测试手段,具有重要意义。

In order to study rock mass permeability characteristics and its mechanics and failure mechanism under high pore water pressure condition, a rock high pressure permeability testing system has been designed and produced. It can perform the test of permeability and correlative mechanics measurement studying for big size and different patterns（cylinder or square column bodies） rock mass or gravel soil under high confining pressure. The max-value of lateral pressure and permeability pressure all can be applied to 30 MPa~ and the axial load can be 4 000 kN. The seepage quantity is obtained through the measurement precision of water seepage volume change quantity, which can save the test time greatly and improve the precision. On the basis of the main control devices of static servo-valve, the entry water pressure of sample can be a stable value under no computer controlled condition. The special pipeline filter and velocity adjust valve have been used to control the flow velocity in the seepage exit. When the controlled velocity equals the sample infiltration velocity, the stable water pressure can be set up, and the stable water pressure difference has been formed between the sample＇s two ends. There has the flexible computer control function, which can monitor the curve variation data and rectify the test plan at any time; and the test steps can be more satisfied than the plan demands. These systems solve the technical problem of permeability and mechanical characteristics test under high pore water pressure and low hydraulic gradient condition. Therefore, this testing system will provide a new test method for the fields such as hydropower engineering, oil and nuclear power industries, and has its significance.