不同粗糙度系数结构面分级剪切蠕变特性  

Graded shear creep characteristics of structural planes with different roughness coefficients

作　　者：刘昂 张迁 华宇 朱军 林文丽 LIU Ang;ZHANG Qian;HUA Yu;ZHU Jun;LIN Wenli(College of Transportation Engineering,Nanjing Tech University,Nanjing 211800,China;Nanjing Intelligent Geotechnical Engineering Technology Research Institute,Nanjing 210018,China;School of Transportation,Southeast University,Nanjing 211189,China)

机构地区：[1]南京工业大学交通运输工程学院,江苏南京211800 [2]南京智慧岩土工程技术研究院,江苏南京210018 [3]东南大学交通学院,江苏南京211189

出　　处：《南京工业大学学报（自然科学版）》2023年第2期220-227,共8页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：江苏省研究生科研与实践创新计划(SJCX22_0465);国家自然科学青年基金(42102319);江苏省自然科学青年基金(BK20210259);中央高校基本科研业务费专项资金(2242022k30055);南京市建设行业科技计划(ks2162)。

摘　　要：掌握结构面剪切蠕变特性的规律是揭示岩体时效变形与破坏的根本途径。通过对Barton标准剖面线第1条和第10条人工水泥砂浆结构面分别开展了恒定法向力条件下的分级剪切蠕变试验,研究了结构面剪切蠕变特性随粗糙度系数(JRC)、法向应力、剪应力的变化规律。同时,采用离散元软件(PFC 2D)对不同粗糙度系数的Barton标准剖面线结构面进行了分级剪切蠕变数值模拟研究。结果表明:在恒定法向力条件下,同一结构面剪切蠕变量、蠕变速率均随剪应力增加而增加;在恒定法向应力及剪应力作用下,剪切蠕变随粗糙度系数增加而减小,结构面剪切蠕变数值模拟结果验证了同样的结论;另外,蠕变变形位移云图结果表明结构面试样沿结构面剪切加载方向,剪切蠕变随距离增加而减小;随着粗糙度系数增加,结构面剪切蠕变破坏模式由滑移摩擦为主逐渐向剪断破坏为主过渡。研究成果可为岩体工程的长期安全稳定性评价提供理论依据。The mastery of shear creep characteristics of structural plane is the fundamental way to reveal the aging deformation and failure of rock mass.The graded shear creep tests of artificial cement mortar structural plane under constant normal force were carried out on the 1st and 10th section of Barton standard profile,respectively.The variation of shear creep characteristics of structural plane with joint roughness coefficient(JRC),normal stress and shear stress was studied.At the same time,the graded shear creep numerical simulations of Barton standard section plane with different roughness coefficients were carried out by discrete element software(PFC 2D).Results showed that under the condition of constant normal force,the shear creep and creep rate of the same structural plane increased with the increase of shear stress,and under the action of constant normal stress and shear stress,the shear creep decreased with the increase of roughness coefficient,the numerical simulation results of shear creep of structural plane verified the same conclusion.In addition,the results of the displacement cloud diagram of creep deformation showed that the shear creep decreased with the increase of distance along the shear loading direction of the structural plane.With the increase of roughness coefficient,the shear creep failure mode of structural plane gradually changed from sliding friction to shear failure.The research results can provide a theoretical basis for the long-term safety and stability evaluation of rock mass engineering.

关 键 词：结构面 粗糙度 剪切蠕变 蠕变速率 粗糙度系数(JRC) 离散元软件 

分 类 号：TU45[建筑科学—岩土工程]