摘要
复杂性岩土工程问题目前尚难以用理论研究方法或数值模拟方法得到准确解答,采用物理模型试验研究方法可较好的弥补上述难题,国内外学者对物理模型试验和三维液压加载装置进行大量的研究。针对小尺寸的装置很难考虑和涉及地质构造因素的影响,大尺寸三维液压加载装置的箱体密封困难等问题,自主研制大型真三维液压加载密封试验装置,装置反力框架整体尺寸为4300mm×3580mm×3150mm(长×宽×高),试验加载箱体外形尺寸为2050mm×1400mm×1300mm,箱体为三向真三轴面加载密封箱体,可进行10MPa地应力及3MPa高压气体条件下煤岩样真三轴加载试验。同时,利用该装置进行煤矿井下巷道掘进过程中,遇到煤厚变异区的煤与瓦斯突出相似模拟试验,研究揭煤过程中瓦斯压力、煤岩应力和温度的变化规律。充气过程中,煤体吸附瓦斯放热使煤层内的温度升高;突出发生前,位于煤厚变异区的应力值较大;突出发生的瞬间,高速气流携带破碎煤岩疾速喷出,突出点附近的瓦斯压力迅速下降;突出发生后,瓦斯解吸和对外膨胀做功使煤层内的温度下降,煤厚变异区构造带附近的温度变化最为显著,下降最大可达7.3℃。顶底板煤岩交界面的应力同时急剧下降,煤厚变异区产生了较高的应力集中,应力值存在短暂升高的过程,最大值达到了1.4MPa,突出煤粉质量比为34.75%。最后,根据试验结果对煤厚变异区突出过程进行能量分析,实验结果符合煤与瓦斯突出的能量失稳判据,揭煤外力扰动会直接或者间接诱导煤与瓦斯突出发生。
At present,the complexity of geotechnical engineering problems is still difficult to be satisfactorily solved by theoretical research or numerical simulation methods.Physical model tests offer a more effective solution to these issues.Extensive research has been conducted on physical model tests and three-dimensional hydraulic loading devices.In response to that small-size devices are difficult to consider and involve the influence of geological structural factors,as well as the difficulty in sealing the box of large-sized three-dimensional hydraulic loading devices,a large-scale true three-dimensional hydraulic loading sealing test device was independently developed.The counter force frame of the device is 4300 mm×3580 mm×3150 mm(length×width×height),and the test loading box has overall dimensions of 2050 mm×1400 mm×1300 mm(length×width×height).This box is a three-way true triaxial loading sealed box capable of conducting true triaxial loading tests on coal and rock samples under 10 MPa in-situ stress and 3 MPa high-pressure gas conditions.Simultaneously,a similar simulation test of coal and gas outbursts during tunneling in the area of coal seam thickness variation was conducted using a dedicated test platform,and the change rules of gas pressure,coal rock stress and temperature were studied.During gas charging,the coal adsorbs gas and releases heat,leading to a rise in temperature within the coal seam.Before the outburst,the stress value in the coal thickness variation area is large.At the moment of the outburst,the high-speed gas flow of the outburst carries the broken coal and rocks out,and the gas pressure near the outburst point drops rapidly.After the outburst,the gas desorption and external expansion work make the temperature in the coal seam drop.The temperature change near the structural belt in the coal thickness variation area is the most significant,the maximum drop can reach 7.3℃.The stress at the coal rock interface of the top and bottom plates decreases sharply at the same time.The coal
作者
高魁
刘泽功
马衍坤
乔国栋
李亮
纪海龙
王有为
GAO Kui;LIU Zegong;MA Yankun;QIAO Guodong;LI Liang;JI Hailong;WANG Youwei(School of Safety Science and Engineering,Anhui University of Science and Technology,Huainan,Anhui 232001,China;Scientific and Technological Research Platform for Disaster Prevention and Control of Deep Coal Mining,Anhui University of Science and Technology,Huainan,Anhui 232001,China)
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2024年第7期1593-1606,共14页
Chinese Journal of Rock Mechanics and Engineering
基金
安徽理工大学煤矿深井开采灾害防治技术科技研发平台开放基金资助(DPDCM2204)
国家自然科学基金资助项目(52374179)
安徽省自然科学基金资助项目(2208085ME125)。
关键词
采矿工程
煤厚变异
煤与瓦斯突出
模拟试验
地质构造
mining engineering
coal seam thickness variation
coal and gas outburst
simulation experiment
geological structure
