常规三轴压缩条件下茅口灰岩流固耦合破坏行为研究  

Study on failure behavior of fluid-solid coupling under conventional triaxial compression for Maokou limestone

作　　者：赵延林[1,2] 唐劲舟 王卫军[1] 程国明 罗世林[1] 付成成[1] 

机构地区：[1]湖南科技大学煤矿安全开采技术湖南省重点实验室,南方煤矿瓦斯与顶板灾害防治安全生产重点实验室,湖南湘潭411201 [2]中国矿业大学煤炭资源与安全开采国家重点实验室,江苏徐州221116 [3]中国地质环境监察院,北京100081

出　　处：《采矿与安全工程学报》2018年第1期205-212,共8页Journal of Mining & Safety Engineering

基　　金：长江科学院开放研究基金项目(CKWV2017508/KY);国家自然科学基金项目(51774131,51434006,41172266);中国矿业大学煤炭资源与安全开采国家重点实验室开放研究基金项目(SKLCRSM16KF12)

摘　　要：采用瞬态法在MTS815岩石力学试验机上进行常规三轴压缩条件下岩石渗透性试验,得到不同围压,不同孔隙水压下茅口灰岩的全应力-应变曲线与渗透压差ΔP的变化曲线,根据试验曲线,分析全应力-应变下茅口灰岩的渗流、强度以及破坏特征。研究表明,岩石在全应力-应变过程中渗透压差ΔP表现为初始下降阶段I,缓慢变化阶段II,非稳定下降阶段III和急剧下降阶段IV共4个阶段,这4个阶段可预测出岩石在全应力-应变过程中渗透率先降低后增加,并在峰值时急剧上升的规律;分别研究了孔隙水压和围压对岩石的峰值强度与变形特性的影响,得到随围压或有效围压的增加,岩石的峰值强度、弹性模量均会增大,但岩石泊松比呈下降趋势的规律,而孔隙水压对岩石峰值强度、弹性模量和泊松比的作用与围压的作用相反。The permeability of Maokou limestone under the conventional triaxial compression condi- tion is measured by MTS815 rock mechanics testing machine, using the transient method. The complete stress-strain and water differential pressure AP curves of Maokou limestone under different confining and hydraulic pressures are captured. According to the experimental curves, the seepage, strength and failure characteristics under the complete stress-strain process are studied. Experimental results show that the water differential pressure AP under complete stress-strain process is characterized as four stages： stage 1 of the initial descent, stage Ii of slowly changing, stage III of non-steady descent and stage IV of sharply descent. These four stages reflect that the rock permeability decreased firstly, then increased, and sharply increased at peak strength point during the complete stress-strain process. The influence of confining pressure and pore water pressure on the peak strength and deformation characteristics of the rock are studied. The peak strength and elastic modulus increase. However, the Poisson＇s ratio tends to decrease with the effective confining pressure. The effect of pore water pressure on peak strength, elas- tic modulus and Poisson＇s ratio is opposite to that of confining pressure.

关 键 词：岩石力学 全应力-应变 渗流 流固耦合 

分 类 号：TU458[建筑科学—岩土工程]