...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Asian earth sciences >Changes in tensile strength and microstructure of loess due to vibration
【24h】

Changes in tensile strength and microstructure of loess due to vibration

机译：黄土的振动引起的抗张强度和微观结构的变化

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Loess soils typically have an open and metastable structure. Humidification and vibration can modify their microstructure and thus influence their mechanical behavior. In the present study, to investigate the influence of train vibration on the tensile strength behavior of loess, the tensile tests were performed on loess specimens that had been vibrated at a low amplitude for a long period using a modified horizontal extensograph. In addition, the microstructures of vibrated and non-vibrated loess specimens before and after the tensile tests were characterized, changes in the loess microstructure due to vibration and that in the tensile test were analyzed. The results show that the relationship between uniaxial tensile strength and water content in soil specimen could be represented using a power function. The axial displacement at failure varies at the same manner as tensile strength with respect to water content. In comparison to intact loess, occurrence of less clay bridges and clay buttresses between aggregates or coarse particles is identified in the disturbed specimens. While aggregates are seen to be a very little more loose in vibrated specimens after the tensile tests than that before the tensile tests. This indicates that vibration reduces the tension-resistance and ductility of loess soil structure, which could be attributed to loss of bonding strength as a result of breakage of clay cementations and disintegration of aggregates. In the tensile test, the soil structure goes through two distinct phases of change, i.e., stretching phase and cracking phase. In the stretching phase, the tensile deformations take place throughout the specimen without altering the contacts between soil particles significantly. In the cracking phase, weak cementations fail to resist tensile deformation and suffer from breakage; once a through-crack is developed, the specimen breaks in two, leading to a catastrophic drop of tensile stress.
机译：黄土土壤通常具有开放和亚稳的结构。加湿和振动会改变其微结构，从而影响其机械性能。在本研究中，为研究列车振动对黄土抗拉强度行为的影响，使用改良的水平引伸计对低振幅长期振动的黄土试样进行了拉伸试验。此外，还对振动和非振动黄土试样在拉伸试验前后的微观结构进行了表征，分析了由于振动引起的黄土微观结构的变化以及在拉伸试验中的变化。结果表明，单轴抗拉强度与土壤试样含水量之间的关系可以用幂函数表示。破坏时的轴向位移与含水量的拉伸强度相同。与完整的黄土相比，在受扰动的标本中，在聚集体或粗颗粒之间出现的粘土桥和粘土支座较少。虽然拉伸试验后的振动试样中的聚集体比拉伸试验前的疏松得多。这表明振动降低了黄土土壤结构的抗拉性和延性，这可能归因于粘土胶结物的破坏和集料的崩解导致粘结强度的损失。在拉伸试验中，土壤结构经历两个不同的变化阶段，即拉伸阶段和开裂阶段。在拉伸阶段，拉伸变形会在整个样本中发生，而不会显着改变土壤颗粒之间的接触。在开裂阶段，弱的胶结作用不能抵抗拉伸变形并遭受破坏。一旦出现贯通裂纹，试样就会断裂为两部分，导致拉伸应力的灾难性下降。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号