粗粒土变形与强度特性大三轴试验研究  

LARGE-SCALE TRIAXIAL TEST STUDY ON DEFORMATION AND STRENGTH CHARACTERISTICS OF COARSE GRAINED MATERIAL

作　　者：禇福永 朱俊高[1,2] 王观琪[3] 刘汉龙[1,2] 

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210098 [2]河海大学岩土工程研究所,江苏南京210098 [3]成都勘测设计研究院坝工处,四川成都610072

出　　处：《山东农业大学学报（自然科学版）》2011年第4期572-578,共7页Journal of Shandong Agricultural University：Natural Science Edition

基　　金：水利部公益性行业科研专项(200801133)"高心墙堆石坝安全性评价技术研究";国家杰出青年科学基金(50825901);国家自然科学基金(50809023)

摘　　要：对两种不同密度的某粗粒土进行了大三轴固结排水剪切试验,分析了粗粒土的应力-应变关系、强度及变形特性,初步探讨了反映剪胀程度的剪胀因子与三者之间的关系,对现有的一些适用于粗粒土的经验公式进行了验证。结果表明:粗粒土低围压下表现出应变软化和剪胀、高围压下表现出应变硬化和剪缩;高围压下最大主应力比和剪胀因子近似呈直线关系;粗粒土的抗剪强度包络线呈非线性,内摩擦角随剪胀因子的增加大致呈线性增加趋势,说明剪胀性的发生会增加粗粒土的抗剪强度;抛物线表达式能较合理地反映侧向应变与轴向应变之间的关系。The triaxial consolidated drained shear test was implemented for the coarse-grained soil of the two kind densities.Based on the test,the stress-strain relationship,strength and deformation property with coarse-grained soil were analyzed,and meanwhile,the influence of shear dilatancy factor which reflects the degree of dilatancy are explored and the versatility of the current empirical formulas was verified.The results indicate： the coarse-grained soil shows strain softening and dilatancy under low confining pressure,but strain hardening under high confining pressure.The relationship of the ratio of maxium principal stress and shear dilatancy is linear under high confining pressure.The failure envelopes of coarse-grained soil present nolinear.With the increase of shear dilatency factor,friction angle of coarse-grained presents linear increase,which shows that shear strength of coarse-grained soil will increase with the occurrence of dilatancy.Parabolic expression can reasonably reflect the relation of lateral strain and axial strain.

关 键 词：粗粒土 大型三轴试验 变形与强度特性 剪胀因子 

分 类 号：S278[农业科学—农业水土工程]