矿业科学学报2026，Vol.11Issue(3)：578-591,14.DOI:10.19606/j.cnki.jmst.2025114
不同温度下粉砂岩力学性能宏细观劣化机制研究
Study on the macro-meso degradation mechanism of mechanical properties of siltstone under different temperatures
摘要
Abstract
This study investigates the degradation effect of high temperature during underground coal gasification on coal seam roof rock.Using a specific heat capacity measuring instrument,XTDIC three-dimensional full-field strain measurement system and scanning electron microscope(SEM),six groups of rock specimens were treated separately for uniaxial compression tests.Results show that 400℃is the critical threshold for the transition of mechanical properties of specimens:At 25℃,200℃and 400℃,increasing temperature led to decreasing porosity,more tightly packed mineral particles,post-poned occurrence of deformation localization,decreasing value of maximum displacement dislocation e-volution and more intense ejection failure;At 600℃,800℃and 1 000℃,specimens exhibited ag-gravated internal damage,significantly increasing porosity,degrading mechanical properties,earlier occurrence of deformation localization and intensified spalling failure.With rising temperature,their u-niaxial compressive strength,elastic modulus and thermal conductivity showed initial increase and sub-sequent decrease.The transformation process of the failure mode is accompanied by varying degrees of ejection-spalling damage.This study reveals the degradation patterns and threshold of siltstone under different temperatures during underground coal gasification,and its macro-meso damage evolution mechanism,providing a theoretical basis for roof stability evaluation and prevetion of engineering disas-ter in high-temperature surrounding rock during gasification.关键词
煤炭地下气化/粉砂岩/温度效应/变形破坏/细观特征Key words
underground coal gasification/siltstone/temperature effect/deformation and failure/me-soscopic features分类
矿业与冶金引用本文复制引用
李伟,辛林,王宪敏,尹大伟,范建国,马彦..不同温度下粉砂岩力学性能宏细观劣化机制研究[J].矿业科学学报,2026,11(3):578-591,14.基金项目
国家自然科学基金(52374211,52274128,52574153) （52374211,52274128,52574153）
泰山学者工程专项基金(tsqn202306199) （tsqn202306199）
