摘要
将分布式光纤传感技术应用于急倾斜煤层采场围岩变形及应力分布特征物理相似模型试验,通过在模型中沿煤层倾向布置传感光纤与沿煤层底板铺设压力传感器,实时监测模型内部变形场与应力场,并结合数值模拟分析了急倾斜煤层顶板应变分布及演化特征。结果表明:工作面上部区域应力值小于下部和中部区域,中部区域应力值最大;随工作面推进,采空区底板应力逐渐释放,应力值不断降低,采空区两侧边界煤柱下方煤层底板应力逐渐升高,且中、下部采空区底板应力恢复程度显著高于上部底板;沿煤层倾向布置的光纤应变曲线呈三段分布,具有前后2处应变波峰区及采空区对应的中部波谷区,前波峰远高于后波峰;工作面中上部顶板变形程度大于下部顶板;数值模拟与光纤检测结果一致,均表现出中上部顶板变形显著大于下部。研究弥补了物理相似模型试验监测手段短板。
The distributed optical fiber sensing technology is applied to the physical similarity model test of hard roof conditions in steep seam.By arranging the sensing optical fiber along the coal seam dip and laying the pressure sensor along the coal seam floor in the model,the deformation field and stress field in the model are monitored in real time,and the strain distribution and evolution characteristics of steep seam roof are analyzed with numerical simulation.The research shows that the stress value in the upper part of the working face is smaller than that in the lower and middle parts,and the stress value in the middle part is the largest.With the advance of the working face,the stress of the goaf floor is gradually released and the stress value is continuously reduced.The stress of the coal seam floor under the boundary pillars on both sides of the goaf is gradually increased,and the stress recovery degree of the middle and lower goaf floor is significantly higher than that of the upper floor;The optical fiber strain curve arranged along the dip of the coal seam is distributed in three sections,with two front and rear strain wave peaks and the corresponding middle wave valley of the goaf.Among them,the front wave peak is much higher than the rear wave peak;The deformation degree of the upper and middle roof of the working face is greater than that of the lower roof.The numerical simulation is consistent with the optical fiber detection results,which show that the deformation of the upper and middle roof is significantly greater than that of the lower.The research makes up for the shortage of monitoring means of physical similarity model test.
作者
王毅
杜文刚
张丁丁
袁强
Wang Yi;Du Wengang;Zhang Dingding;Yuan Qiang(College of Resources and Security,Chongqing Vocational Institute of Engineering,Chongqing 402260,P.R.China;College of Energy Engineering,Xi'an University of Science and Technology,Xi'an 710054,P.R.China;College of Resources and Security,Chongqing University,Chongqing 400044,P.R.China)
出处
《地下空间与工程学报》
CSCD
北大核心
2024年第4期1327-1333,1344,共8页
Chinese Journal of Underground Space and Engineering
基金
重庆市教委科研基金(KJQN202203401)
重庆工程职业技术学院校级科研项目(KJB202318)。
关键词
相似模拟试验
急倾斜煤层
底板应力
变形监测
光纤传感
similar simulation test
steep seam
bottom plate stress
deformation monitoring
fiber optic sensing
