考虑主应力方向的Q_(2)原状黄土定向剪切试验研究  

Experimental Study of Directional Shear of Q_(2)in Situ Loess Considering the Direction of Principal Stress

作　　者：王睢 钟祖良[2,3] 赵鹏[4] 高志华[4] 刘超 Wang Sui;Zhong Zuliang;Zhao Peng;Gao Zhihua;Liu Chao(Ningbo University of Technology,Ningbo Zhejiang,315211,P.R.China;School of Civil Engineering,Chongqing University,Chongqing 400045,P.R.China;Key Laboratory of New Technology for Construction of Cities in Mountain Area,Ministry of Education,Chongqing University,Chongqing 400045,P.R.China;Chang’an University,School of Architectural Engineering,Xi’an 710061,P.R.China)

机构地区：[1]宁波工程学院土木地下系,浙江宁波315211 [2]重庆大学土木工程学院,重庆400045 [3]山地城镇建设与新技术教育部重点实验室,重庆400045 [4]长安大学建筑工程学院,西安710061

出　　处：《地下空间与工程学报》2023年第4期1160-1168,共9页Chinese Journal of Underground Space and Engineering

基　　金：山地城镇建设与新技术教育部重点实验室开放项目(LNTCCMA-20200104);宁波市自然科学基金(2019A610394);广西防灾减灾与工程安全重点实验室开放项目(2019ZDK005)。

摘　　要：为了研究在定向剪切下主应力偏转角对Q_(2)原状黄土强度与变形特性的影响,探讨了在定向剪切荷载作用下Q_(2)原状黄土的变形与强度特性,对比分析了重塑黄土与原状黄土结构性对剪切特性和非共轴特性的影响。结果表明:由于原状黄土内部结构性差异,当主应力偏转角α在0°和15°时,应变增量方向角随着α的增加而逐渐增加,非共轴性增强;当主应力偏转角α在30°~90°之间时,应变增量方向角随着α的增加而逐渐减小,非共轴性减弱,整体上呈先增强后减弱的趋势。该原状黄土达到破坏时的总广义应变值较小,通常为2%左右达到峰值强度,然后迅速发生较大变形而破坏。In order to study the effect of principal stress deflection angle on the strength and deformation characteristics of Q_(2) in-situ loess under directional shear.The deformation and strength characteristics of Q_(2) in-situ loess under directional shear loading were researched,and the in-situ properties in comparison with remodeled loess were analyzed.The effect of structural properties of loess on shear properties and non-coaxial properties was analyzed in comparison with remodeled loess.The test shows that due to the difference of internal structural properties of in-situ loess,when the main stress deflection angleαis between 0 and 15°,the directional angle of strain increment gradually increases with the increase ofα,and the non-coaxial property increases;when the main stress deflection angleαis between 30°and 90°,the directional angle of strain increment gradually decreases with the increase ofα,and the non-coaxial property decreases.The overall trend is that it first strengthens and then weakens.At the same time,because the structural properties within the in-situ loess are not destroyed before the peak strength,the total generalized strain value when reaching the damage is small,and the generalized shear strain value when reaching the peak strength is also small,usually about 2%reaching the peak strength,and then the damage occurs rapidly with larger deformation.

关 键 词：Q_(2)原状黄土 主应力偏转角 中主应力比 剪切特性 非共轴特性 

分 类 号：TU411.3[建筑科学—岩土工程]