Experiment of mesostructure and hydrologic characteristics of weakly cemented soft rocks in western China

Authors

ZHANG Jiafan, Department of Mechanics, Xi'an University of Science and Technology, Xi'an 710054, China
CHENG Shufan, Department of Mechanics, Xi'an University of Science and Technology, Xi'an 710054, China
WANG Huan, Department of Mechanics, Xi'an University of Science and Technology, Xi'an 710054, China
GAO Zhuang, Department of Mechanics, Xi'an University of Science and Technology, Xi'an 710054, China
ZHOU Feiwen, Department of Mechanics, Xi'an University of Science and Technology, Xi'an 710054, China
ZHOU Hongwen, College of Urban Construction and Safety Engineering, Shanghai Institute of Technology, Shanghai 201418, ChinaFollow

Abstract

In order to accurately grasp the hydrologic characteristics of weakly cemented soft rocks in western China, the hydraulic and mechanical properties of red sandstone collected from northern Shaanxi mining area were tested. Based on the scanning image of scanning electron microscope(SEM), the mesostructural characteristics of the rocks were analyzed, and the relationship between the mesostructure of rocks and its macroscopic hydrologic characteristics was established. The results show that red sandstone has obvious characteristics of water saturation and water absorption and expansion, and its softening coefficient is 0.64. Under the action of pressure water erosion and dry and wet cycle, the properties of saturated red sandstone will be further degraded, which will be characterized by the decrease of strength and elastic modulus and the increase of mass loss rate. On the microscale, the relationship between red sandstone particles is relatively loose and has obvious weak cementitious structure characteristics. Generally speaking, the coupling effect of hydrophilic mineral dissolution and weak cementitious structure failure leads to the special macroscopic hydrologic characteristics of red sandstone. The results of this paper can provide certain theoretical support for the treatment and safe construction in weak cemented soft rock.

Keywords

weakly cemented soft rock, hydraulic property, mesostructure, property degradation, SEM, coalfield of northern Shaanxi

DOI

10.3969/j.issn.1001-1986.2020.03.017

Recommended Citation

ZHANG Jiafan, CHENG Shufan, WANG Huan, et al. (2020) "Experiment of mesostructure and hydrologic characteristics of weakly cemented soft rocks in western China," Coal Geology & Exploration: Vol. 48: Iss. 3, Article 18.
DOI: 10.3969/j.issn.1001-1986.2020.03.017
Available at: https://cge.researchcommons.org/journal/vol48/iss3/18

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