| 摘要: |
| 利用大型三轴仪选用一种典型堆石料，通过设置4种级配、4种相对密度开展一系列不同围压作用下的大型三轴压缩试验，以研究级配、密度、应力状态等因素对堆石料强度与变形特性的影响。基于以上试验，对比分析不同级配、不同密度、不同围压条件下堆石料的应力变形特性，结果表明：试样颗粒越粗，剪切过程中试样越呈现应变硬化和压缩变形特性，随着颗粒逐渐变细，应变软化和剪胀特性愈加明显；堆石料强度与变形特性不仅与其密实和所处的应力状态有关，而且初始级配对其强度与变形特性有显著影响；堆石料强度包络线符合幂函数关系，并通过分析计算验证了其合理性与正确性。分析结果为进一步研究堆石料的状态相关剪胀理论及状态相关本构模型奠定了基础。 |
| 关键词: 堆石料 级配 密度 强度 变形 |
| DOI： |
| 分类号:TU521.2 |
| 基金项目:国家自然科学基金资助项目(51179105) |
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| Experimental studies on strength and deformation behaviors of rockfill materials considering particle gradation |
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LI Xiao-mei1,2, GUAN Yun-fei2, LING Hua2, WU Ying-li2
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1.Department of Geotechnical Engineering, Tongji University, Shanghai;2.Nanjing Hydraulic Research Institute, Nanjing
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| Abstract: |
| In order to study the influences of gradation, density and stress state on the strength and deformation behaviors of the rockfill materials, some typical materials are selected for large triaxial shearing tests, so a series of laboratory tests are designed under the conditions of different gradations, densities and confining pressures by the large triaxial equipment. According to the experimental results, and by analyzing and comparing the stress-strain characteristics, we can get many important conclusions: firstly, the larger the grain size of samples, the more obvious the strain hardening and compression behaviors among the shearing process, and on the contrary, the smaller the grain size of samples, the more obvious the strain softening and dilatancy properties; secondly, the strength and deformation of the rockfill materials are related to the density and stress state, and the influence of the sample initial gradation is so large that it should be paid more attention to; the last but not the least, the intensity envelope of the rockfill materials changes by a power function relationship, and the rationality and validity is verified by analyzing test results and calculation results. The research results of this paper are the basis of further studies of the state-dependent dilatancy theory and state-dependent constitutive model of the rockfill materials. |
| Key words: rockfill materials gradation density strength deformation |
