循环剪切作用下泥质软岩本构模型研究  

Study on Constitutive Model of Muddy Soft Rock under Cyclic Shear

作　　者：刘新荣[1,2] 蔺广义 何春梅 许彬[1,2] 黄俊辉 Liu Xinrong;Lin Guangyi;He Chunmei;Xu Bin;Huang Junhui(School of Civil Engineering,Chongqing University,Chongqing 400045 T P.R.China;National Joint Engineering Research Center for Prevention and Control of Environmental Geological Hazards in the TGR Area,Chongqing 400045,P.R.China;College of Architectural Engineering,Neijiang Normal University,Neijiang,Sichuan 641000,P.R.China)

机构地区：[1]重庆大学土木工程学院,重庆400045 [2]库区环境地质灾害防治国家地方联合工程研究中心,重庆400045 [3]内江师范学院建筑工程学院,四川内江641000

出　　处：《地下空间与工程学报》2022年第2期386-396,共11页Chinese Journal of Underground Space and Engineering

基　　金：国家自然科学基金(41972266)。

摘　　要：库区微震频发现象使泥质软岩受循环剪切动力作用。基于分数阶西原模型,将Able黏壶进行改进,获得相应条件下的本构模型,并通过泥质软岩试样循环剪切试验对该本构模型进行了验证。研究表明:(1)原有分数阶西原本构模型可归纳为本模型正弦函数(循环作用)为零时的特殊解;(2)模型表现出较好的适用性(R^(2)∈(0.96,0.98)),且方程曲线具备试验曲线的“单双拐点”特征;(3)模型主要影响因素为分数阶阶数n,其中稳定型方程n∈(0,0.6)、破坏型方程n∈(0.6,1.0);(4)随n的增加,抗剪模量G与黏滞系数η大致呈现降低趋势,可较好反映宏观现象;(5)从参数扰动的角度解释了以往文献出现的η随n增加可能表现出的无规律波动现象。研究成果可为微震条件下含泥质软岩边坡长期稳定性控制提供理论参考。The frequent occurrence of microseisms in the reservoir area makes the muddy soft rock subject to cyclic shear dynamic action. Based on the fractional Nishihara model(FNM), the adhesive pot of Able is improved, and the constitutive model under the corresponding conditions is further obtained, which is verified by the cyclic shear test of the muddy soft rock sample. The research shows that:(1) the original FNM can be summed up as a special solution when the sinusoidal function(cyclic action) is zero in the proposed mode.(2) The model shows good applicability(R^(2)∈(0.96,0.98)), and the equation curve has the characteristics of “single and double turning points”, which can be found in the test.(3) The main influencing factor of the model is fractional order n, in which the stability condition n∈(0,0.6), the failure condition n∈(0.6,1.0).(4) With the increase of n, the shear modulus G and viscosity coefficient η decrease, which can better reflect the macroscopic phenomenon.(5) From the point of view of parameter disturbance, the irregular fluctuation of η with the increase of n in the previous literature is explained. The research results can provide theoretical reference for the long-term stability control of muddy soft rock slope under microseismic condition.

关 键 词：频发微震 泥质软岩 本构模型 循环剪切试验 参数反演 

分 类 号：TU452[建筑科学—岩土工程]