冲击荷载下饱水板岩拉伸力学特性及能耗规律  

Study on tensile mechanical properties and energy consumption law of saturated slate under impact loads

作　　者：刘运思[1,2] 何楚韶 傅鹤林[3] 王世鸣[2] 雷勇[1,2] 彭亚雄 LIU Yunsi;HE Chushao;FU Helin;WANG Shiming;LEI Yong;PENG Yaxiong(Hunan Provincial Key Laboratory of Geotechnical Engineering for Stability Control and Health Monitoring,Hunan University of Science and Technology,Xiangtan,Hunan 411201,China;School of Civil Engineering,Hunan University of Science and Technology,Xiangtan,Hunan 411201,China;School of Civil Engineering,Central South University,Changsha,Hunan 410075,China)

机构地区：[1]湖南科技大学岩土工程稳定控制与健康监测省重点实验室,湖南湘潭411201 [2]湖南科技大学土木工程学院,湖南湘潭411201 [3]中南大学土木工程学院,湖南长沙410075

出　　处：《岩石力学与工程学报》2020年第11期2226-2233,共8页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(51704109,51604109);湖南省自然科学基金项目(2020JJ5179)。

摘　　要：为研究饱水状态下层状板岩的动态拉伸力学特性及能量耗散规律,通过压杆直径为50 mm的SHPB系统进行巴西圆盘劈裂试验,研究水、层理倾角及加载率对板岩的动态拉伸强度、破坏模式及能量耗散的影响。研究结果表明:(1)随着加载率的增加,板岩动态拉伸强度及耗散能密度均提高;(2)当加载率低于395 GPa·s-1时,饱水板岩的拉伸强度低于干燥板岩,岩体强度呈现饱水软化现象;当加载率高于395 GPa·s-1时,饱水板岩的拉伸强度高于干燥板岩,岩体强度呈现饱水强化现象;(3)当加载角度θ=0°~15°时,饱水板岩为拉伸破坏;θ=30°~90°时,饱水板岩为拉伸剪切组合破坏;θ=75°和90°时,随着加载率的增加,饱水板岩的动态拉伸强度增幅更快,耗散能及耗散率最高;(4)冲击荷载下饱水板岩的耗散能密度高于干燥板岩。In order to study the dynamic tensile mechanical properties and energy dissipation mechanisms of layered slate under saturated conditions,Brazilian disc split test was performed by using SHPB system with a 50 mm diameter rod,and the influence of water,bedding angle and loading rate on the dynamic tensile strength,failure mode and energy dissipation of slate was studied. The research results show that the dynamic tensile strength and the dissipated energy density of slate increase with increasing the loading rate. When the loading rate is lower than 395 GPa·s-1,the tensile strength of saturated slate is lower than that of dry slate,and the strength of the rock mass is softening. However,when the loading rate is higher than 395 GPa·s-1,the tensile strength of saturated slate is higher than that of dry slate,and the strength of the rock mass presents a strengthening phenomenon. Saturated slate shows tensile failure mode and combined tensile and shear failure mode when the loading angle θ is in the ranges of 0°–15°and 30°–90°. When θ = 75° and 90°,the dynamic tensile strength of saturated slate increases faster as the loading rate increases,and at the same time,the energy dissipation and the dissipation rate are the highest. The dissipated energy density of saturated water slate is higher than that of dry slate under impact loads.

关 键 词：岩石力学 冲击荷载 巴西圆盘劈裂试验 饱水板岩 动态拉伸强度 能量耗散 

分 类 号：TU45[建筑科学—岩土工程]