CRD工法隧道单次拆除临时中隔壁长度研究  

Study on the Removable Length of Temporary Partition Wall Single Demolition in CRD Method Tunnel

作　　者：蒋荣兵 JIANG Rongbing(China Railway 18th Bureau Group Third Engineering Co.,Ltd.,Zhuozhou 072750,China)

机构地区：[1]中铁十八局集团第三工程有限公司,河北涿州072750

出　　处：《国防交通工程与技术》2025年第2期26-30,共5页Traffic Engineering and Technology for National Defence

摘　　要：为了最大化加快工期、保证既有地下管线安全,研究了单次可拆除CRD工法隧道临时中隔壁的长度,通过建立三维有限元分析模型,计算分析了不同单次拆除临时支撑长度下地下管线的变形,结合变形控制标准,确定了单次拆除临时中隔壁的长度为25 m,并对施工全过程进行受力分析和验算。研究结果表明:(1)CRD工法一次性拆除临时支撑25 m并每2 m间隔保留1榀拱架的方案是安全可行的。(2)拆除临时支撑时,间隔保留的中隔壁钢拱架轴力急剧增大,必须重点关注其受压稳定性。(3)拆除下部临时中隔壁后,拱腰以下初支弯矩和拱顶弯矩增加。(4)拆除下部临时中隔壁后,原来临时中隔壁承担的部分轴力向初支转移,初支的轴力增大。现场施工验证了方案的可行性。To accelerate the construction schedule while ensuring the safety of underground pipelines,this study investigates the maximum removable length of temporary partition wall in tunnel constructed using the CRD method.A three-dimensional finite element analysis model was developed to analyze the deformation of underground pipelines under different removal lengths of temporary support.Based on deformation control standards,the optimal removable length of the temporary partition wall was determined to be 25 meters,and a comprehensive stress analysis was conducted for the entire construction process.The findings of this study indicate that:①Removing 25 meters of temporary support at one time,while retaining one arch frame at every 2-meter interval,is a safe and feasible approach.②During the removal of temporary support,the axial force of the retained steel arch frames in the partition wall increases sharply,necessitating close monitoring of its compressive stability.③After removing the lower temporary partition wall,the bending moments of the primary support below the arch waist and at the arch vault increase due to the loss of the temporary support.④After removing the lower temporary partition wall,part of the axial force previously borne by the temporary partition wall is transferred to the primary support,resulting increase of axial force in the primary support.The field construction verification confirmed the feasibility of this removal scheme.

关 键 词：隧道 CRD工法 临时中隔壁 拆除 沉降变形 净空收敛 初支安全 

分 类 号：U455.4[建筑科学—桥梁与隧道工程]