摘要
为研究原状黄土的各向异性特征,以延安新区某边坡Q3原状黄土为研究对象,开展不同取样方向原状黄土直剪试验和无侧限抗压强度试验,获取原状黄土应力—应变关系曲线、抗剪强度、无侧限抗压强度及强度指标,对比分析原状黄土的各向异性规律。研究结果表明:低应力条件下水平方向原状黄土抗剪强度明显小于深度方向试样,而高应力条件下两者之间的差异减小;取样方向对原状黄土低应力抗剪强度指标影响显著,且对黏聚力的影响高于内摩擦角;深度方向试样无侧限抗压强度明显高于水平试样,且压剪破坏后深度方向试样表面产生的斜裂缝少于水平方向试样;建议在黄土工程设计与稳定性分析过程中,应重视原状黄土强度各向异性的影响。
In order to study the anisotropic characteristics of undisturbed loess,taking the undisturbed loess Q3 from a slope in Yan′an New District as the study object,the direct shear test and unconfined compressive strength test of undisturbed loess in different sampling direction are carried out to obtain the stress-strain relationship curve,shear strength,unconfined compressive strength and strength index,and the anisotropy law of undisturbed loess is compared and analyzed.The results show that the shear strength of undisturbed loess in the horizontal direction is significantly smaller than that of the vertical direction sample under low stress conditions,while the difference between the two directions is reduced under high stress conditions.The sampling direction has a significant effect on the low stress shear strength index of undisturbed loess,and the effect of sampling direction on the cohesion is more obvious than that of internal friction angle.The unconfined compressive strength of depth direction sample is significantly higher than that of horizontal sample,and the inclined cracks on the surface of the depth direction sample are less than the horizontal sample after compressive shear damage.It should pay attention to the effect of strength anisotropy of undisturbed loess in the process of loess engineering design and stability analysis.
作者
邱明明
郑隆君
田宇轩
周恒祎
李明泽
Qiu Mingming;Zheng Longjun;Tian Yuxuan;Zhou Hengyi;Li Mingze(School of Architectural Engineering,Yan′an University,Yan′an 716000,China)
出处
《工程勘察》
2023年第9期14-20,共7页
Geotechnical Investigation & Surveying
基金
陕西省重点研发计划资助项目(2020ZDLSF06-03)
陕西省教育厅服务地方专项计划项目(21JC035)
延安市重点研发计划项目(2019ZCSY-006)
延安大学科研计划资助项目(CXY202006,YDY2020-36)
国家级大学生创新创业训练计划项目(202110719036)。
关键词
原状黄土
各向异性
抗剪强度
无侧限抗压强度
变化规律
undisturbed loess
anisotropy
shear strength
unconfined compressive strength
changing rule
