强度相近异性结构面的剪切特性  

Shear Properties of Anisotropic Structural Surfaces with Similar Strength

作　　者：崔志猛 邓志颖 张丙武 余灏 李龙 CUI Zhimeng;DENG Zhiying;ZHANG Bingwu;YU Hao;LI Long(School of Highway,Chang’an University,Xi’an 710064,China;Guangzhou Cheng’an Highway&Bridge Testing Co.,Ltd.,Guangzhou 511431,China)

机构地区：[1]长安大学公路学院,西安710064 [2]广州诚安路桥检测有限公司,广州511431

出　　处：《工业建筑》2022年第6期133-139,共7页Industrial Construction

摘　　要：为加深对异性结构面力学性质的认识,基于Barton标准剖面线制作了4种粗糙系数的石膏-砂浆结构面试样,两种材料的强度相近,在3种法向应力下进行室内直剪试验和数值模拟。根据得到的两类剪切变形曲线,并对强度相近异性结构面的峰值剪切强度随粗糙系数和法向应力增长而变化的规律及变形特征进行分析;依据数值模拟结果总结了强度相近异性结构面的剪切破坏模式。研究发现强度相近的异性结构面剪切存在如下特征:低粗糙系数结构面的剪切应力-位移曲线到达峰值后即进入残余变形阶段,而较高粗糙系数结构面的剪切应力-位移曲线存在明显的软化阶段;剪切应力增长得快慢与粗糙系数、法向应力正相关;在不同法向应力下,随粗糙系数的增大,先后发生爬坡破坏、爬坡-啃断破坏、啃断破坏。To further understand the mechanical properties of anisotropic structural surfaces,the specimens with gypsum-mortar structural surfaces in four joint roughness coefficients were made based on the standard Barton’s section lines of structural surfaces.Particularly,gypsum and mortar had the similar uniaxial compressive strength.Two kinds of curves between shear stress and displacement were obtained by indoor direct shear tests under three kinds of normal stress.Consequently,the change laws for peak shear strength of specimens with gypsum-mortar structural surfaces with the increase of joint roughness coefficients and normal stress were analyzed.Based on the numerical simulating results,the shear failure modes of anisotropic structural surfaces with similar strength were summarized.The curves between shear stress and displacement of anisotropic structural surfacess with lower roughness coefficients developed to the residual deformation stage after reaching peak values,while the curves of specimens with higher roughness coefficients evolved to the obvious softening stage.The growth rates of shear stress was positively correlated with roughness coefficients and normal stress.Under different normal stress,climbing failure,climbing-gnawing failure and gnawing failure occured successively to the anisotropic structural surfaces with similar strength as the roughness coefficient increased.

关 键 词：强度相近异性结构面 粗糙系数 剪切变形 峰值剪切强度 剪切破坏模式 

分 类 号：TU45[建筑科学—岩土工程] TU528[建筑科学—土工工程]