【摘要】 为了研究粘土岩的气体渗透率特性,利用瞬间脉冲法测量原理,研究开发出低渗透率气体测量的三轴设备.并详细地介绍分析各种影响气体测量中的关键技术参数(气体压力、压力增量、温度和气体容器大小),结合反分析法准确地确定岩石的渗透率.借助该设备,粘土岩在不同应力水平条件的气体渗透率被跟踪测量.实验结果表明该设备可以准确测量低渗透岩石(<10-21m2),该地质材料的气体渗透率随偏应力增加而减少,但即使材料已经处于损伤阶段,这种变化也非常微弱,因此气体渗透率的变化不能作为一个有效的损伤变量.更多还原

【Abstract】 In order to investigate the gas permeability of mudstones,a new experimental setup has been built and developed.This system is based on the ’pulse test’ principle and it allows to measure the very low permeability of rock under real triaxial conditions.Several key technique parameters,such as the gas pressure,gas increment pressure,temperature and the reservoir volume,will be discussed and optimized.The back analysis method has been used to accurately estimate the gas permeability.The experimental results of a mudstone sample show the well performance of the experimental setup and the gas permeability of this material is very little(<10-21 m2) and it decreased with the increase of the deviator stress;but this variation is very small,although the material is damaged.So the variation of gas permeability of the mudstone can not be considered as a damage variable.更多还原