土工基础

土工基础 ›› 2020, Vol. 34 ›› Issue (6): 740-744.

• 测试技术 • 上一篇    下一篇

颗粒形状对粗砂直剪特性影响研究

赵书辉1,2，魏厚振3，吴永洁1,2，王 睿1,2   

  1. （1.桂林理工大学土木与建筑工程学院，广西桂林 541004；2.广西岩土力学与工程重点实验室，广西桂林 541004；3.中国科学院武汉岩土力学研究所 岩土力学与工程国家重点实验室，武汉 430071）
  • 收稿日期:2019-12-30 修回日期:2020-07-15 出版日期:2020-12-30 发布日期:2020-12-25
  • 通讯作者: 魏厚振（1980－），男，博士，副研究员，研究方向为珊瑚岛礁岩土力学与工程。
  • 作者简介:赵书辉（1992－），男，硕士研究生，研究方向为岩土工程。

Influence of Particle Shape on the Direct Shear Properties of Coarse Sand Samples

ZHAO Shuhui1,2, WEI Houzheng3, WU Yongjie1,2， WANG Rui1,2   

  1. (1.College of Civil Engineering and Architecture, Guilin 541004;
    2.Key Laboratory of Soil and Rock Mechanics and Engineering, Guilin 541004;
    3.State Key Laboratory of Geomechanics and Engineering, 
    Wuhan Institute of Soil and Rock Mechanics, Chinese Academic of Sciences, Wuhan 430071)
  • Received:2019-12-30 Revised:2020-07-15 Online:2020-12-30 Published:2020-12-25

摘要： 岩土材料物理力学性质变化的本质是其细观结构发生改变，颗粒形状作为砂土细观结构的重要参数，必然会对其力学性质产生影响。借助颗粒形貌扫描设备对3种不同形状的粗砂进行测试，并通过室内直剪试验探究颗粒形状对粗砂抗剪强度的影响。结果表明：4种颗粒形状参数敏感性由大到小依次为：长宽比>扁平度>磨圆度>球度；粗砂颗粒形状愈规则，其颗粒重排列所主导的峰值内摩擦角就愈小，所以峰值内摩擦角随颗粒形状规则程度的提高而减小；颗粒形状愈规则，剪切后期颗粒间的滑动摩擦力就愈小，相应的残余内摩擦角就愈小。

关键词: 粗砂, 直剪试验, 颗粒形状, 抗剪强度

Abstract: The change of physical and mechanical properties of the geomaterials can be attributed to the change of microstructures of materials. Three soil samples with different grain shapes were studied by a grain shape scanning device. The influence of the grain shape on the shear strength of coarse sand samples are evaluated by the direct shear tests. The results indicate that, based on their sensitivity, the ranking of the four grain shape parameters is: length to width ratio>flatness ratio>wearing ratio>roundness ratio. When the shape of the coarse sand is more “regular”, the smaller of the internal friction angle for the particle rearrangement. As a result, the internal friction angle with the regularity of the grain particles will reduce. After reaching the peak shear strength, the sliding frictions among particles is smaller for the more “regular shaped” particles and then the smaller residual internal friction angle.


Key words: Coarse Sand, Direct Shear Tests, Grain Shapes, Shear Strength

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