Physico-mechanical characteristics of Q2 loess in South Plateau of Jingyang(PDF)
长安大学学报（自然科学版）[ISSN:1006-6977/CN:61-1281/TN]
- Issue:
- 2016年05期
- Page:
- 60-66
- Research Field:
- 桥梁与隧道工程
- Publishing date:
Info
- Title:
- Physico-mechanical characteristics of Q2 loess in South Plateau of Jingyang
- Author(s):
- DUAN Zhao; PENG Jian-bing; LENG Yan-qiu
- 1. College of Geology and Environment, Xi’an University of Science and Technology, Xi’an 710054， Shaanxi， China；2. School of Geology Engineering and Geomatics， Chang’an University， Xi’an 710054， Shaanxi， China
- Keywords:
- geotechnical engineering; physico-mechanical characteristic; shear test; Q2 loess; South Plateau of Jingyang
- PACS:
- TU43;P642
- DOI:
- -
- Abstract:
- Loess is a kind of common natural building materials in western China. The physico-mechanical characteristics of loess show significant differences in space which is affected by forming environment. Physicalmechanical characteristics research of typical loess will provide a reference for regional engineering construction. The physico-mechanical characteristics of Q2 loess in typical slope of South Plateau of Jingyang were investigated by laboratory tests which include laser particle size analysis, soil convention experiment X-ray diffraction analysis, permeability test, triaxial shear test and ring shear test. The physico-mechanical characteristics of Q2 loess were systematically investigated. The results show that Q2 loess is a kind of special soil with large pore structure. Fine grains are the major component. The natural water content, density and void ratio of Q2 loess change regularly with depth. The weight percentage of primary minerals and secondary minerals are found to be 50% and 47%, respectively in loess. The plastic limit water content is (15.4±1.2)% and the liquid limit water content is (26.8±0.7)%. Q2 loess has the characteristics of lower permeability and anisotropy, and its effective permeability coefficient is 3.455×10-4 cm/s. The water content has remarkable impact on stress-strain behaviors, shear strength parameters and failure mode. Plastic limit water content is considered as a threshold between brittle deformation and plastic deformation of Q2 loess. The residual strength is greatly influenced by shear rate and normal stress, and the residual strength parameters decrease with the increase of shear rate and have no relation with normal stress.
Last Update: 2016-10-06