摘要
煤体开采前后可能会受到不同程度水作用的影响,其力学性质将产生变化,进而影响煤体承载能力,关系到采矿安全。通过不同浸水时长煤样的巴西劈裂实验,研究了水对煤岩抗拉强度及其破坏特征的影响。试验结果表明:煤样含水率随浸水时长增加而不断增大,20d后含水率稳定在0.77%左右;浸水时长为5d的煤样抗拉强度较未浸水煤样增大了0.57MPa,浸水时长大于5d的煤样抗拉强度逐渐降低,最终趋于平稳;煤岩类孔隙比与抗拉强度呈负相关关系,相同类孔隙比的煤样抗拉强度随浸水时长增加而减小;煤样破坏后破裂线宽度及面积随浸水时长增加而减小。
The coal mass may be affected by water action in different degrees before and after mining, which could change the mechanical properties, so as to further affect the bearing capacity of coal mass and threaten the safety production of coal mine.The soaking effects on the tensile strength and failure characteristics of coal petrography were studied by the Brazil splitting tests of coal samples with different soaking time. The results showed that the moisture rate of samples increased with the in- crease of soaking time, and the moisture rate was stable at about 0.77~~ after 20 days. The tensile strength of samples with 5 days soakingtime increased by 0.57 MPa compared with that of the un-soaking coal. The tensile strength of samples soaked more than 5 days decreased gradually and finally tended to be stable. Similar void ratio of rock had a negative correlation with the tensile strength. The tensile strength of coal samples with the same similar void ratio decreased with the increase of soaking time, and the width and area of fracture line also decreased with the increase of soaking time after the coal samples failure.
作者
马宏发
尹大伟
陈绍杰
刘兴全
陈兵
MA HongJa;YIN Dawei;CHEN Shaojie;LIU Xingquan;CHEN Bing(State Key Laboratory of Mining Disaster Prevention and Control Co-Founded by Shandong Provence and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao, Shandong 266590, Chin)
出处
《矿业研究与开发》
CAS
北大核心
2018年第4期56-60,共5页
Mining Research and Development
基金
国家自然科学基金项目(51474134
51774194)
山东省自然科学杰出青年基金资助项目(JQ201612)
山东省重点研发计划项目(2016GSF11704)
关键词
煤
浸水作用
抗拉强度
类孔隙比
破坏特征
Coal, Soaking effect, Tensile strength, Similar void ratio, Failure characteristics
