循环载荷下饱和岩石的摩擦阻力研究  

Internal friction resistance of saturated rocks under cyclic loading

作　　者：张汉羽 陈佼佼[3,4] 陈运平 刘怀山[1] ZHANG Hanyu;CHEN Jiaojiao;CHEN Yunping;LIU Huaishan(Laboratory for Marine Geology,Qingdao National Laboratory for Marine Science and Technology,Qingdao 266061,China;Hainan Key Laboratory of Marine Georesource and Prospecting,Institute of Deep-sea Science and Engineering,Chinese Academy of Sciences,Sanya 572000,China;Computational Geosciences Research Centre,School of Earth Sciences and Info-Physics,Central South University,Changsha 410083,China;Sanya Institute of Hydrogeology and Engineering Geology Investigation,Sanya 572000,China)

机构地区：[1]中国海洋大学海底科学与探测技术教育部重点实验室,青岛266100 [2]中国科学院深海科学与工程研究所海南省海底资源与探测技术重点实验室,三亚572000 [3]中南大学地球科学与信息物理学院计算地球科学研究中心,长沙410083 [4]三亚水文地质工程地质勘察院,三亚572000

出　　处：《海洋地质与第四纪地质》2022年第3期194-203,共10页Marine Geology & Quaternary Geology

基　　金：国家自然科学重点基金“近海底地震海洋学立体探测与成像基础研究”(91958206);三亚崖州湾科技城重大项目“海底分布式光纤地震系统及应用示范”(SKJC-2020-01-009)。

摘　　要：在循环载荷下岩石发生应力-应变的非线性弹性行为是普遍的,孔隙流体、载荷频率、围压、层理方向是造成岩石应力应变滞后、能量衰减、刚性变化等特征的重要外部变量。基于来自大庆、南京、合肥等地的砂岩样品,利用电液闭环伺服控制压机系统,开展了不同饱和流体砂岩的应力-应变滞回曲线、不同载荷频率和饱和流体对岩石的衰减、不同层理方向加载和卸载对岩石杨氏模量影响的实验对比研究,阐明了饱和岩石的非线性响应特征,揭示了外界影响因素对岩石产生非线性形变的作用机制,探讨了岩石内部触面间摩擦阻力在岩石发生非线性形变过程中发挥的媒介作用,并推断接触面颗粒之间的摩擦阻力可能是导致岩石发生衰减、滞后等非线性行为的内在因素。本研究拟通过岩石内部小尺度的摩擦作用与构造尺度断层面上的摩擦滑移相似性,来揭示地震发生时岩体失稳的动力学过程。The stress-strain loop hysteretic nonlinear behavior of a rock is generally adopted in uniaxial cyclic loading experiments.Pore fluid,cyclic loading frequency,confining pressure and bedding direction are important external variables that cause stress and strain hysteresis,energy attenuation and rigidity change of rocks.In this paper,three comparative experiments have been carried out under the Material Testing System(MTS)for the stress-strain hysteresis with different saturated fluids,the rock energy attenuation by loading different frequency stress and saturated fluids,and Young’s modulus effect for the sandstones with different bedding directions sampled from Daqing,Nanjing,Hefei,etc.Based on the results,we clarified the nonlinear elastoplastic response characteristics of saturated rocks,and revealed the nonlinear deformation mechanism induced by external factors.And the mediating role of friction resistance on internal particle contact surfaces during rocks nonlinear elastic deformation process is proved.It is inferred that the sliding friction resistance of particles in macro-cracks may be the main internal factor resulted in the attenuation and hysteresis of rocks.This paper attempts to further reveal the dynamics process of earthquakes and rock instability based on the similarity of frictional sliding between the fine-scale rock particles and the earth-scale tectonic faults.

关 键 词：非线性弹性响应 杨氏模量 摩擦阻力 围压 滞后 

分 类 号：P589.1[天文地球—岩石学]