力学与实践 ›› 2021, Vol. 43 ›› Issue (1): 57-65.DOI: 10.6052/1000-0879-20-277

• 应用研究 • 上一篇    下一篇

沉积方向和粒径组成对砂土力学特性的影响1)

罗强2), 尹畅, 张虎, 李晓磊, 马可栓   

  1. 南阳师范学院土木建筑工程学院,河南南阳 473061
  • 收稿日期:2020-07-07 修回日期:2020-09-02 发布日期:2021-02-23
  • 通讯作者: 2)罗强,副教授,主要从事土力学本构理论方面的研究工作。 E-mail: luoqiang1212@sina.com
  • 基金资助:
    1)国家自然科学基金(51609117),河南省教育厅科学技术研究重点项目(14B560023)和河南省高等学校青年骨干教师培养计划(2018GGJS118)资助

EFFECTS OF SEDIMENTARY DIRECTION AND PARTICLE SIZE COMPOSITION ON MECHANICAL BEHAVIORS OF SAND1)

LUO Qiang2), YIN Chang, ZHANG Hu, LI Xiaolei, MA Keshuan   

  1. School of Civil Engineering and Architecture, Nanyang Normal University, Nanyang 473061, Henan, China
  • Received:2020-07-07 Revised:2020-09-02 Published:2021-02-23

摘要: 运用砂土毛细效应所形成的假凝聚力制备具有不同沉积方向的试样, 开展三轴固结排水剪切试验, 研究粒径组成对初始各向异性砂土力学特性的影响,分析了粒径组成、沉积方向、强度特性和体积变化之间的相互关系。研究结论表明,试样剪切带的形成受到颗粒级配的影响,它是应力应变关系中陡降阶段的产生原因。沉积方向对粗砂和细砂的偏应力峰值强度均有影响,对残余强度的影响受制于颗粒级配。沉积方向与试样破坏面接近时,试样强度低、剪胀变形小且更容易破坏,粒径组成对砂土三轴剪切力学特性的影响更显著。

关键词: 初始各向异性, 粒径组成, 沉积方向, 剪切试验

Abstract: Using the pseudo cohesive force formed by the capillary effect of the sand to prepare samples with different sedimentary directions, a series of the triaxial consolidation drainage shear tests are performed to study the influence of the granulometric composition on the mechanical properties of the initial anisotropic sand. The relationship among the granulometric composition, the sedimentary direction, the strength characteristics and the volume change is analyzed. The results show that the formation of the shear band is affected by the particle size distribution, which is the cause of the sharp drop stage in the stress-strain relationship. The sedimentation direction has an effect on the deviatoric stress peak strength of the coarse sand and the fine sand, and the effect on the residual strength is limited by the particle size distribution. When the sedimentary direction is close to the failure surface of the sample, the strength of the sample is low, the dilatancy deformation of the sample is small and it is easier to be damaged, and the granulometric composition has a more significant influence on the triaxial shear mechanical behavior of the sand.

Key words: initial anisotropy, granulometric composition, sedimentary direction, shear test

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