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.