基于双重介质渗流-应力耦合模型的高压压水试验渗透参数反演  

Inversion of Permeability in High Pressure Packer Test under Hydro-Mechanical Coupling of Dual Media

作　　者：王锦国[1] 韩智颖 程伟 黄瑞瑞 尤琳 杨蕴[1] WANG Jin-guo;HAN Zhi-ying;CHENG Wei;HUANG Rui-rui;YOU Lin;YANG Yun(School of Earth Science and Engineering,Hohai University,Nanjing 211100,China;Power China Kunming Engineering Corporation Limited,Kunming 650051,China)

机构地区：[1]河海大学地球科学与工程学院,南京211100 [2]中国电建集团昆明勘测设计研究院有限公司,昆明650051

出　　处：《长江科学院院报》2024年第8期113-119,156,共8页Journal of Changjiang River Scientific Research Institute

基　　金：江苏省自然科学基金项目(BK20221507)。

摘　　要：高压压水试验过程中岩体易发生水力劈裂产生裂隙,岩体内部孔隙、裂隙双重导水,渗流场和应力场相互作用,导致岩体渗透参数的时空变异性。基于高压压水试验反演渗透参数需考虑双重介质渗流-应力耦合作用下产生裂隙前后渗透系数的变化规律,利用渗流-应力耦合数值模型结合工程现场高压压水试验数据进行参数反演,计算得到不同压力阶段下灰岩岩体渗透率。主要结论如下:发生水力劈裂前,随着注液压力的增大,渗透率及孔隙水压力在不同压力阶段之间分界明显,渗透率反演值与规程公式计算值相近;发生水力劈裂后,岩体渗透率增大约2倍,孔隙介质渗透率和通过的流量出现陡减现象。Hydraulic fracturing easily occurs in rock masses under high-pressure packer tests,involving dual water conduction via pores and cracks.This interaction between the seepage and stress fields results in spatial-temporal variations in rock mass permeability parameters.For accurate permeability parameter inversion during high-pressure packer tests,it is recommended to consider the change in permeability coefficient before and after fracture occurrence under hydro-mechanical coupling of dual media.A hydro-mechanical coupling numerical model is employed to simulate high-pressure packer tests,and parameter inversion is conducted using on-site test data to calculate limestone permeability across different pressure stages.Key findings include:before hydraulic fracturing,as injection pressure increases,permeability and pore water pressure sees distinct boundaries among different pressure stages,with inverted permeability closely aligning with specified formula values.After hydraulic fracturing,rock mass permeability increases by about 2 times,accompanied by sharp declines in matrix pore medium permeability and flow rates.

关 键 词：高压压水试验 双重介质 渗流-应力耦合 渗透率 水力劈裂 

分 类 号：P642.3[天文地球—工程地质学]