摘要
二叠系炭质页岩软弱夹层在石灰岩矿山中分布广泛,因其力学强度低、流变效应显著等特点常成为石灰岩矿山边坡的薄弱部位,严重影响边坡的稳定性。以某典型石灰岩矿山边坡中的二叠系炭质页岩软弱夹层为研究对象,开展了常规剪切试验和剪切蠕变试验,对比分析了软弱夹层的常规抗剪强度与长期抗剪强度,以揭示软弱夹层的蠕变特性,结果表明:在常规剪切试验中,正应力越大,峰值剪切强度、峰值位移越大;在剪切蠕变试验中,相同正应力条件下,软弱夹层的蠕变速率随着剪应力的增大而增大,蠕变特性表现为初始、稳态、加速蠕变三个变形阶段;软弱夹层长期抗剪强度明显小于常规抗剪强度,黏聚力的降幅较大,对时间的敏感度较高。
The weak interlayers of the Permian carbonaceous shale are widely found in the limestone mines.Due to its low mechanical strength and remarkable rheological effect,the weak interlayers often become the vulnerable parts of the limestone mine slope and pose a serious threat to the stability of the slope.In this paper,the weak interlayer of Permian carbonaceous shale in a typical limestone mine slope was taken as the research object.The conventional shear tests and shear creep tests were carried out,and the comparative analysis of conventional shear strength and long-term shear strength of the weak interlayer were undertaken to reveal the creep deformation characteristics of the weak interlayer.The results show that the higher the positive stress,the higher the peak shearing strength and peak displacement during the conventional shear test.In the performance of shear creep test,under the same positive stress condition,the creep deformation rate of weak interlayer increases as the shear stress rises,and the creep characteristics presents three deformation stages:initial creep,steady creep and accelerated creep.The long-term shear strength of weak interlayer was obviously lower than normal shearing strength.The sharp drop of cohesion was highly sensitive to time.
作者
尤耿明
王光进
孔祥云
胡航
陈志斌
You Gengming;Wang Guangjin;Kong Xiangyun;Hu Hang;Chen Zhibin(Faculty of Public Safety and Emergency Management,Kunming University of Science and Technology,Kunming Yunnan 650093,China;National and Local Joint Engineering Research Center for Green Comprehensive Utilization of Metal Ore Tailings Resources,Faculty of Land Resources Engineering,Kunming University of Science and Technology,Kunming Yunnan 650093,China)
出处
《化工矿物与加工》
CAS
2022年第2期56-59,共4页
Industrial Minerals & Processing
基金
浙江湖州南太湖精英计划"边坡灾害监测预警平台研发及产业化"领军型创新团队。
关键词
软弱夹层
抗剪强度
剪切蠕变
炭质页岩
蠕变特性
剪切试验
weak interlayer
shearing strength
shear creep deformation
carbonaceous shale
shear creep behavior
shear test
