高地应力水平岩层隧道初期支护适应性研究  

Study on Adaptability of Initial Support of Tunnel in High Stress Horizontal Strata

作　　者：袁铁 YUAN Tie(China State Railway Group Co.Ltd,Beijing 100844,China)

机构地区：[1]中国国家铁路集团有限公司,北京100844

出　　处：《铁道工程学报》2024年第9期55-59,66,共6页Journal of Railway Engineering Society

摘　　要：研究目的:蒙华铁路宜川县境内隧道地层多为水平砂泥岩互层地层,区域水平地应力高,在地应力和水平岩层共同作用下,隧道初期支护发生大面积起皮、开裂、掉块、钢架扭曲,对施工带来较大安全隐患,针对高地应力水平岩层采取什么类型的措施是亟须研究解决的问题。本次共研究了常规支护、加强型支护、加筋底板+长锚杆、限阻耗能型支护四种支护类型,结合3DEC离散元软件以及现场实际变形应力量测数据对四种支护类型效果进行对比分析,从而得出高地应力水平岩层应对工程措施。研究结论:(1)高地应力水平岩层开裂主要表现为拱顶喷混凝土剥皮、掉块、钢架扭曲;(2)单一加强支护参数方案、加筋底板+长锚杆支护方案对控制变形收敛具有效果,但拱部仍然存在开裂掉块现象,不能完全解决施工安全风险;(3)限阻耗能型支护可达到释放围岩压力的效果,限阻结构变形后初期支护未出现开裂现象;(4)在高地应力水平岩层中采用限阻耗能型支护在经济性、安全性上成效显著,推广应用效果良好。Research purposes:The tunnel strata in Yichuan County of Menghua Railway are mostly horizontal sand and mudstone interbedded strata,the regional horizontal in-situ stress is high,under the joint action of in-situ stress and horizontal rock strata,the initial support of the tunnel occurs in a large area of peeling,cracking,falling blocks,and steel frame distortion,which brings greater safety hazards to the construction,and what type of measures to take for the high geostress horizontal rock strata is a problem that needs to be studied urgently.The four types of support types of conventional support,reinforced support,reinforced floor+long anchor,and limited resistance and energy dissipation support were studied.Combined with the 3DEC discrete element software and the actual deformation stress force measurement data in the field,the effects of the four types of support were compared and analyzed,and the engineering measures for rock strata with high geostress level were obtained.Research conclusions:(1)The cracking of the rock layer with high geostress level is mainly reflected in the peeling of the shotcrete of the vault,the falling of blocks and the distortion of the steel frame.(2)The single reinforced support parameter scheme and the reinforced bottom plate+long anchor support scheme have the effect on controlling the deformation convergence,but the arch still has the phenomenon of cracking and falling blocks,which cannot completely solve the construction safety risk.(3)The resistance-limiting energy-dissipating support can achieve the effect of releasing the pressure of the surrounding rock,and the initial support does not crack after the deformation of the resistance-limiting structure.(4)The use of resistance-limiting energy-dissipating support in rock formations with high geostress levels has achieved remarkable results in economy and safety,and the promotion and application effect is good.

关 键 词：水平岩层 地应力 开裂 初支 限阻器 

分 类 号：U45[建筑科学—桥梁与隧道工程]