doi:10.16186/j.cnki.1673-9787.2020.5.2

Received:2019/12/20

Revised:2019/03/26

Published:2020/09/15

Study on mechanical characteristics of sandstone with natural weak plane inShendong coal field

LI Huigui1, LI Huamin2, XU Guosheng1

1.College of Mining Engineering， Guizhou University of Engineering Science ，Bijie 551700 ， Guizhou， China;2.School of Energy Science and Engineering，Henan Polytechnic University ，Jiaozuo  454000 ， Henan， China

Abstract:In order to study the influence of natural weak face on the physical and mechanical characteristics of sandstone in Shendong coal field，the basic top medium-grained sandstone of No. 2-2 coal in Bulianta coal mine was taken as the research object. Direct tension，direct shear and uniaxial compression tests of intact sandstone and sandstone with weak surface were carried out by using CMT5000 gate computer controlled electronic universal testing machine，RDS-200XL automatic servo controlled rock direct shear/residual shear tester and RMT-150C mechanical testing machine. X-ray diffraction and scanning electron microscopy were used to analyze the composition， microstructure and element characteristics. Results showed that：The natural weak plane had no effect on the longitudinal wave velocity， compressive strength and residual shear strength. P-wave velocity， uniaxial compressive strength and residual shear strength decreased by 0.4%，1.4% and 3.2% ， respectively. Natural weak surfaces had significant effects on direct tensile strength， peak strain， peak shear strength and modulus of elasticity. The peak tensile strength decreased by 83.1% ， the peak tensile strain decreased by 82.7% ，the peak shear strength decreased by 12.6%，and the elastic modulus decreased by 7.3 %.The results of this study were helpful to further understand the law of movement，breaking and force transmission of this kind of roof with natural weak plane.

Key words:natural weak plane;sandstone;mechanical characteristic;Shendong coal field

神东矿区含天然弱面砂岩的力学特征研究_李回贵.pdf