张玉等：复杂应力路径下裂隙泥岩渗透演化规律试验研究 909· -Deviatoric stress loading and unloading Increasing confining pressure Permeability ratio:RI sample --Permeability ratio:R2 sample Confining Confining Confining Confining 45 1.2 pressure pressure pressure pressure 7.3 MPa 8.3 MPa 9.3 MPa 10.3 MPa 40 36 1.0 30 30 30 30 26.1 30 26.1 0.8 27 26.1 26.1 0.6 18 5 0.4 9 8.1 8.1 8.1 8.1 10 0.2 0 0 0 0 8 12 Loading level Cycle number 图15围压、偏压增长下渗透性测试方案（渗透压力：3.5MPa) 图13偏应力循环加卸载和渗透率比关系 Fig.15 Schematic of permeability test for increasing confining pressure Fig.13 Relationship between cyclic loading and unloading of deviatoric and deviatoric stress(Liquid pressure:3.5 MPa) stress and permeability ratio 1017、0.11×1017、0.07×10~17、0.02×1017m2.裂隙闭 1.2 RI sample 合导致渗透率降低幅度的总体变化趋势为随围压 1.04 R2 sample 增加逐渐减小，故高围压作用下渗透率趋于稳定： R1和R2岩样稳定渗透率分别为1.04×10~19m2和 0.8 0.11×10-17m2 该阶段无偏应力作用下R1和R2岩样初始渗透 率分别为2.06×1019m2和0.37×10~17m2(渗透压力 0.4 3.5MPa,围压7.3MPa).前期应力加载导致岩样裂隙 03 闭合，R1和R2岩样渗透率比下降趋势基本一致（图18）. Cycle number 图14偏应力0MPa加卸载和渗透率比关系 3渗透率演化力学模型 Fig.14 Relationship between loading and unloading and permeability 3.1力学模型构建 ratio under deviatoric stress,0 MPa 裂隙泥岩渗透率K由裂隙渗透率K和基质渗 围压7.3、8.3、9.3和10.3MPa作用下，偏应力 透率Km组成： 加载引起R1和R2岩样渗透率分别降低了0.73× K=Kt+Km (2) 1019、0.59×1019、0.46×1019、0.02×10-19m2和0.08× 基质渗透率变化较小，故认为试验过程中基 -Deviatoric stress loading Deviatoric stress loading e-Permeability evolution -Permeability evolution Confining Confining Confining Confining Confining Confining Confining Confining pressure pressure pressure pressure pressure pressure pressure pressure 7.3 MPa 8 3 MPa 9.3 MPa 10.3 MPa 7.3 MPa 83 MPa 93 MPa 10.3 MPa 36 2.2 36 0.5 2.06 (a) (b) 2.0 0.38 1.74 ! 04g 1.80 0.370.320.32 18 49 1.6 .50 028 0.23 1.4 0.25 0.19 1 1.23 0.21 0.17 0.2 0.13 0.12 9 1.02 1.2 9 0.17 1.15 1.04 1.02 Le 0.1 .09.09 1.0 0.12 .120.11 0.95 08 8 12 1 8 12 16 Loading level Loading level 图16 围压、偏压增长和渗透率关系.(a)R1岩样：(b)R2岩样 Fig.16 Relationship between increasing confining pressure and deviatoric stress and permeability:(a)RI sample;(b)R2 sample围压 7.3、8.3、9.3 和 10.3 MPa 作用下，偏应力 加载引起 R1 和 R2 岩样渗透率分别降低了 0.73× 10−19、0.59×10−19、0.46×10−19、0.02×10−19 m 2 和 0.08× 10−17、0.11×10−17、0.07×10−17、0.02×10−17 m 2 . 裂隙闭 合导致渗透率降低幅度的总体变化趋势为随围压 增加逐渐减小，故高围压作用下渗透率趋于稳定； R1 和 R2 岩样稳定渗透率分别为 1.04×10−19 m 2 和 0.11×10−17 m 2 . 该阶段无偏应力作用下 R1 和 R2 岩样初始渗透 率分别为 2.06×10−19 m 2 和 0.37×10−17 m 2 （渗透压力 3.5 MPa，围压 7.3 MPa）. 前期应力加载导致岩样裂隙 闭合，R1 和R2 岩样渗透率比下降趋势基本一致（图18）. 3    渗透率演化力学模型 3.1    力学模型构建 Kf Km 裂隙泥岩渗透率 K 由裂隙渗透率 和基质渗 透率 组成： K=Kf+Km （2） 基质渗透率变化较小，故认为试验过程中基 0 0.2 0.4 0.6 0.8 1.0 1.2 0 5 10 15 20 25 30 35 40 45 0 1 2 3 Permeability ratio Deviatoric stress/MPa Cycle number Deviatoric stress loading and unloading Permeability ratio: R1 sample Permeability ratio: R2 sample 图 13    偏应力循环加卸载和渗透率比关系 Fig.13    Relationship between cyclic loading and unloading of deviatoric stress and permeability ratio 0.2 0.4 0.6 0.8 1.0 1.2 0 1 2 3 Permeability ratio Cycle number R1 sample R2 sample 图 14    偏应力 0 MPa 加卸载和渗透率比关系 Fig.14     Relationship  between  loading  and  unloading  and  permeability ratio under deviatoric stress, 0 MPa 0 9 18 27 36 0 4 8 12 16 Deviatoric stress/MPa Loading level 0 8.1 26.1 0 26.1 30 8.1 0 30 30 26.1 Confining pressure 7.3 MPa 30 26.1 8.1 8.1 0 Increasing confining pressure Confining pressure 8.3 MPa Confining pressure 9.3 MPa Confining pressure 10.3 MPa 图 15    围压、偏压增长下渗透性测试方案（渗透压力：3.5 MPa） Fig.15    Schematic of permeability test for increasing confining pressure and deviatoric stress（Liquid pressure：3.5 MPa） 2.06 1.80 1.49 1.33 1.74 1.50 1.23 1.15 1.42 1.11 1.04 0.95 1.02 1.03 1.02 1.04 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 0 9 18 27 36 0 4 8 12 16 Permeability/(10−19 m2 ) Deviatoric stress/MPa Loading level Deviatoric stress loading Permeability evolution Confining pressure 7.3 MPa Confining pressure 8.3 MPa Confining pressure 9.3 MPa Confining pressure 10.3 MPa (a) 0.37 0.38 0.32 0.28 0.32 0.25 0.23 0.21 0.19 0.17 0.17 0.12 0.13 0.12 0.12 0.11 0 0.1 0.2 0.3 0.4 0.5 0 9 18 27 36 0 4 8 12 16 Permeability/(10−17 m2 ) Deviatoric stress/MPa Loading level Deviatoric stress loading Permeability evolution Confining pressure 7.3 MPa Confining pressure 8.3 MPa Confining pressure 9.3 MPa Confining pressure 10.3 MPa (b) 图 16    围压、偏压增长和渗透率关系. （a）R1 岩样；（b）R2 岩样 Fig.16    Relationship between increasing confining pressure and deviatoric stress and permeability: (a) R1 sample; (b) R2 sample 张    玉等： 复杂应力路径下裂隙泥岩渗透演化规律试验研究 · 909 ·