煤岩三轴蠕变-渗流-吸附解吸实验装置的研制及应用

Development and application of tri-axial creep-seepage-adsorption and desorption experimental device for coal

为研究受载含瓦斯煤岩流变过程中的渗流规律和煤体瓦斯吸附解吸特性,自主研制了煤岩三轴蠕变-渗流-吸附解吸实验装置,该装置主要由主机、伺服加载系统、三轴压力室、孔压控制系统、吸附解吸系统、温度控制系统、变形测量系统以及安全防护系统等8个部分组成,其最大轴压为500 k N、最大围压为50 MPa、最高加热稳定温度为90℃,试件尺寸为?50 mm×100 mm。该装置具有以下主要优势:能实现煤岩孔隙率的测试、煤岩力学参数测试、煤岩瓦斯吸附解吸实验和受载含瓦斯煤的蠕变-渗流等多种实验,功能强大、性能稳定、测试准确;采用了滚珠丝杠加载方式,满足了蠕变-渗流等实验的长期加载需求,最长加载时间能达2个月以上;配备了高低温控制系统,能实现煤岩试样进气端、出气端和三轴压力室3处的气体温度保持一致,有效避免了温度变化所导致的气体流量上的测量误差。同时利用该装置分别开展了煤样孔隙率测试、受载含瓦斯煤样解吸特性和含瓦斯煤样的蠕变-渗流实验研究,实验验证了该装置在功能上的多样性和在测试上的准确性和可靠性。

A tri-axial creep-seepage-adsorption and desorption experimental device has been developed to study seep-age law and gas adsorption and desorption characteristics in the process of loaded gas bearing coal rheology. It is com-posed of testing main machine,servo-controlled loading system,triaxial compression chamber,pore pressure controlsystem,adsorption and desorption system,temperature control system,deformation monitoring system and safe guardsystem. The maximum axial pressure is 500 k N,and the maximum confining pressure is 50 MPa. The heating tempera-ture can reach as high as 90 ℃;and the dimensions of tested cylinder samples are？50 mm×100 mm. The advantagesof the device are as follows：1 It can be used to test the porosity and mechanical parameters of coal and to carry outthe gas adsorption desorption and creep-seepage experiments of loaded gas-bearing coal and other experiments as well.The device,in addition,is powerful in function,stable in performance and accurate in testing. 2 It can also be fitted toconduct creep-seepage experiments for long time because of adopting the ball screw loading mode. And the maximumloading time can be more than two months. 3 The device is equiped with high and low temperature control system.And it can be used to keep the constant temperature at the gas inlet,gas outlet and the triaxial compression chamber,which can effectively avoid the messurement error caused by temperature variation. Experiments of coal porosity tes-ting,gas desorption characteristics and creep-seepage lawof loaded coal are conducted using this device. These conclu-sions validate the functional diversity,accuracy and reliability in testing on the device.