A new theory for determining large deformation area of roof at intersection and verification analysis  

确定交岔点顶板大变形区域的新理论模型及验证分析

作　　者：WU Yi-yi GAO Yu-bing MA Xiang ZHANG Xing-xing HE Man-chao 武毅艺;高玉兵;马翔;张星星;何满潮

机构地区：[1]College of Construction Engineering,Jilin University,Changchun 130026,China [2]State Key Laboratory for Tunnel Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China [3]School of Mechanics and Civil Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China [4]School of Energy and Mining Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China

出　　处：《Journal of Central South University》2025年第2期656-677,共22页中南大学学报(英文版)

基　　金：Project(52204164)supported by the National Natural Science Foundation of China;Project(2021QNRC001)supported by the Young Elite Scientists Sponsorship Program by CAST,China。

摘　　要：The intersection is a widely used traffic line structure from the shallow tunnel to the deep roadway,and determining the subsidence hidden danger area of the roof is the key to its stability control.However,applying traditional maximum equivalent span beam(MESB)theory to determine deformation range,peak point,and angle influence poses a challenge.Considering the overall structure of the intersection roof,the maximum equivalent triangular plate(METP)theory is proposed,and its geometric parameter calculation formula and deflection calculation formula are obtained.The application of the two theories in 18 models with different intersection angles,roadway types,and surrounding rock lithology is verified by numerical analysis.The results show that:1)The METP structure of the intersection roof established by the simulation results of each model successfully determined the location of the roof’s high displacement zone;2)The area comparison method of the METP theory can be reasonably explained:①The roof subsidence of the intersection decreases with the increase of the intersection angle;②The roof subsidence at the intersection of different roadway types has a rectangular type>arch type>circular type;③The roof subsidence of the intersection with weak surrounding rock is significantly larger than that of the intersection with hard surrounding rock.According to the application results of the two theories,the four advantages of the METP theory are compared and clarified in the basic assumptions,mechanical models,main viewpoints,and mechanism analysis.The large deformation inducement of the intersection roof is then explored.The J 2 peak area of the roof drives the large deformation of the area,the peak point of which is consistent with the center of gravity position of the METP.Furthermore,the change in the range of this peak is consistent with the change law of the METP’s area.Hence,this theory clarifies the large deformation area of the intersection roof,which provides a clear guiding basis for its initial suppor从地表浅部隧道至深部巷道,交岔点是应用广泛的交通线路结构,确定交岔点顶板的下沉隐患区是其稳定性控制的关键。而应用传统的等效跨度理论分析变形的范围、峰值点及角度影响等因素存在困难。考虑交岔点顶板的整体结构,提出了等效三角板理论,并得到了等效三角板的几何参数计算式和挠度计算式。通过数值分析验证两种理论在不同交叉角度、不同巷道类型和不同围岩岩性下18个模型中的应用情况,结果表明:1)基于各模型模拟结果建立的交岔点顶板等效三角板结构成功确定了顶板的高位移区位置;2)等效三角板理论的面积对比法可合理解释:①交岔点顶板下沉量随交叉角度增大而减小;②不同巷道类型交岔点的顶板下沉量存在矩形类>拱形类>圆形类;③围岩软弱的交岔点顶板下沉量明显大于围岩较硬的交岔点。根据两种理论应用结果,在基本假设、力学模型、主要观点及机理分析上对比阐明了等效三角板理论的4点优势。由此探究交岔点顶板大变形诱因,得到J 2峰值带驱动区域大变形,其峰值点与等效三角板的重心点位置相一致,其范围的变化与等效三角板面积的变化规律相符。等效三角板理论明确了交岔点顶板的大变形区域,为其初期支护设计、中期监测和后期局部补强提供了清晰的指导依据。

关 键 词：roadway intersection roof deformation equivalent span theory triangular plate structure numerical analysis stress partial tensor 

分 类 号：TD322[矿业工程—矿井建设] TD353