Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Journal

Microstructure

Earth Sciences

Publication Year

Articles 1 - 7 of 7

Full-Text Articles in Engineering

Experimen On Mechanical Properties Of Various Graded Collapse Column Fills, Liu Weitao, Du Yanhui, Pang Lifu, Meng Xiangxi, Shen Jianjun, Hu Yingying Apr 2023

Experimen On Mechanical Properties Of Various Graded Collapse Column Fills, Liu Weitao, Du Yanhui, Pang Lifu, Meng Xiangxi, Shen Jianjun, Hu Yingying

Coal Geology & Exploration

In order to study the mechanical properties of collapse column fill under different consolidation pressures and grain compositions. Base on similar simulated rock-soil mass sample under different states of geotechinal consolidation test preparing, we investigated the mechanical characteristics and microstructure evolution mechanism of collapse column filling by conducting the triaxial loading test, mercury intrusion porosimetry and scanning electron microscopy in different states of rock-soil mass. The results show that the rock-soil mass has obvious shaping characteristics and the stress-strain curve can be divided into four stages: pore compaction stage, stable deformation stage, deformation failure stage and creep-like stage. The compressive …


Characteristics And Formation Mechanisms Of Microstructures In Coal Treated With Co2 Phase Transition Fracturing, Cao Yunxing, Zhang Xinsheng, Zhang Junsheng, Guo Shuaifang, Meng Bingbing Apr 2023

Characteristics And Formation Mechanisms Of Microstructures In Coal Treated With Co2 Phase Transition Fracturing, Cao Yunxing, Zhang Xinsheng, Zhang Junsheng, Guo Shuaifang, Meng Bingbing

Coal Geology & Exploration

CO2 phase transition fracturing (CPTF) is a newly developed technique for coal mine gas control and is characterized by high efficiency, high coal seam permeability, a high gas drainage rate, and outburst elimination. The core of CPTF is reinforced fracturing and the pressure-relief and permeability-enhancement effects of coal seams under high-pressure dynamic loading. Nevertheless, there is a lack of studies on the morphological characteristics and formation mechanisms of newly formed fractures. Current observation and description of the underground fractures on a centimeter-meter scale primarily aim to reveal the fracturing and permeability-enhancement mechanisms of low-permeability coal seams. However, the study …


Study On The Microscopic Mechanism Of The Loess Improved By Quicklime, Xie Xiao, Wang Luyao, Deng Lejuan, Zhang Guowei Dec 2021

Study On The Microscopic Mechanism Of The Loess Improved By Quicklime, Xie Xiao, Wang Luyao, Deng Lejuan, Zhang Guowei

Coal Geology & Exploration

To investigate the influence of lime content on loess strength and its microscopic mechanism, different proportions of lime were used to improve loess. Through direct shear test, mercury intrusion porosimetry and scanning electron microscopy, the strength characteristics and microstructure changes of compacted loess and modified loess with different lime contents were analyzed qualitatively and quantitatively, and the microscopic mechanism of lime-improved loess was analyzed in depth. The results show that the shear strength parameters of lime-improved loess increases first and then decreases with the increase of lime contents. The cohesive force and internal friction angle reach the maximum when the …


Pulverized Coal-Controlling Method Based On Supermolecular Film In Cbm Well, Wu Ying, Li Xiaonan, Liu Zixiong, Liu Rumin Dec 2020

Pulverized Coal-Controlling Method Based On Supermolecular Film In Cbm Well, Wu Ying, Li Xiaonan, Liu Zixiong, Liu Rumin

Coal Geology & Exploration

Correctly understanding the micro-scale fracture characteristics of the Lower Cambrian shale and the evolution law of acoustic emission signals are of great reference value in the study of shale mechanical characteristics, fracture mechanism and shale gas development and utilization. In this paper, based on digital image processing technology, the non-uniform characterization of quartz-filled shale is carried out, and a numerical model is established using the real rock fracture analysis system RFPA2D-DIP to simulate the failure process of shale under different confining pressures. The test results show that under the micro-scale structure, the shale failure mode can be roughly …


Numerical Experiment On Damage And Fracture Of Shale Based On Micro-Scale, Cui Hengtao, Wu Zhonghu, Lou Yili, Zuo Yujun, Sun Wenjibin, Liu Hao Oct 2020

Numerical Experiment On Damage And Fracture Of Shale Based On Micro-Scale, Cui Hengtao, Wu Zhonghu, Lou Yili, Zuo Yujun, Sun Wenjibin, Liu Hao

Coal Geology & Exploration

Correctly understanding the micro-scale fracture characteristics of the Lower Cambrian shale and the evolution law of acoustic emission signals are of great reference value in the study of shale mechanical characteristics, fracture mechanism and shale gas development and utilization. In this paper, based on digital image processing technology, the non-uniform characterization of quartz-filled shale is carried out, and a numerical model is established using the real rock fracture analysis system RFPA2D-DIP to simulate the failure process of shale under different confining pressures. The test results show that under the micro-scale structure, the shale failure mode can be roughly …


The Microscopic Fabric Characteristics Of Biaxial Compression Test Of Typical Argillaceous Siltstone In Badong Formation, Xiao Zunqun, Wang Xin, Tang Dongsang, Dong Qiongying, Jiang Yinan, Yang Kai, Cao Tongtong, Deng Zhen Apr 2020

The Microscopic Fabric Characteristics Of Biaxial Compression Test Of Typical Argillaceous Siltstone In Badong Formation, Xiao Zunqun, Wang Xin, Tang Dongsang, Dong Qiongying, Jiang Yinan, Yang Kai, Cao Tongtong, Deng Zhen

Coal Geology & Exploration

Based on the indoor biaxial compression test of argillaceous siltstone, a numerical model of PFC2D particle flow was established. The model considered the particle shape of the argillaceous siltstone samples. Five typical particle shapes were selected according to the scanning electron microscope, and the circular particles were selected. A stable numerical sample of a given porosity was randomly generated together. The parallel bond contact model was selected between the particles, and the elastic modulus, Poisson’s ratio and peak stress were selected to calibrate the meso-parameters of the saturated and natural argillaceous siltstone samples under different confining pressures, and then the …


Effect Of Clay Content On Shear Strength Of Loess, Wang Li, Li Xi'an, Hong Bo, Du Shaoshao, Zhang Hangbo, Zhao Ning Jun 2019

Effect Of Clay Content On Shear Strength Of Loess, Wang Li, Li Xi'an, Hong Bo, Du Shaoshao, Zhang Hangbo, Zhao Ning

Coal Geology & Exploration

The experimental research about effect of different clay content on shear strength of loess was carried out to reveal the influence of clay content on shear strength and its microscopic mechanism, and then a scientific basis for engineering practice of loess was provided. Self-made wet sieve device under negative pressure was applied to screen loess samples with different clay content. Different clay content of the loess samples were made to the same dry density, but with different moisture content using static pressure method, and then were taken direct shear test. The results show that with the increase of moisture content, …