(1 西南科技大学土木工程与建筑学院, 绵阳 621010; 2 中建二局第一建筑工程有限公司, 北京 100176)

摘要: 某类清水混凝土大尺寸异型洞体工程对施工精度要求比普通混凝土结构高得多,常规模板支撑体系已不能满足该类洞体施工对内壁的高精度要求,综合分析选用格构柱⁃H 型钢梁框架作为该洞体模板支撑结构体系. 对结构进行有限元分析,并根据模板体系装配误差及变位和变形进行实时工艺微调,以满足支撑结构体系对装配精度的控制要求,进行现场原位加载试验,确定模板支撑体系的可行性. 分析结果表明:有限元分析中最大挠度为28mm,为满足精度要求需对顶部位移较大模板实施预起拱,且对应力及变形较大杆件进行加强. 试验中模板挠度均较小,最大挠度为 2. 82mm,满足混凝土施工对精度指标控制要求. 二级加载后支撑杆件上最大应变仅为47. 3με,应力水平较低,处于弹性工作状态. 该模板支撑结构体系满足高精度的大型清水混凝土洞体工程施工精度的指标要求,能用于现场施工.

关键词: 清水混凝土洞体; 钢模板支撑结构; 高精度施工; 现场原位加载试验

中图分类号:TU318 文献标志码:A 文章编号:1002⁃848X(2022)08⁃0099⁃06

DOI:10. 19701 / j.jzjg.LS210134

Experimental study on bearing capacity of steel formwork support structure in large concrete tunnel

CHU Yunpeng1, ZHONG Yan1, SUN Xinhui1, LIU Xin2

(1 School of Civil Engineering and Architecture, Southwest University of Science and Technology, Mianyang 621010, China;2 China Construction Second Engineering Bureau First Construction Engineering Co., Ltd., Beijing 100176, China)

Abstract: The construction accuracy of a certain type of fair⁃faced concrete large⁃size special⁃shaped tunnel project is muchhigher than that of ordinary concrete structure, and the conventional formwork support system cannot meet the high⁃precision requirements of the tunnel construction on the inner wall. The lattice column⁃H steel beam frame was selected asthe formwork support structure system of the tunnel. The finite element analysis of the structure was carried out, and thereal⁃time process fine⁃tuning was carried out according to the assembly error, displacement and deformation of the formworksystem to meet the control requirements of the support structure system on the assembly accuracy. The in⁃situ load test wascarried out to determine the feasibility of the formwork support system. The results of analysis show that: the maximumdeflection in the finite element analysis is 28mm. In order to meet the accuracy requirements, it is necessary to pre⁃arch theformwork with large displacement at the top, and strengthen the bars with large stress and deformation. The deflection offormwork is small in the test, and the maximum deflection is 2. 82mm, which meets the requirements of precision indexcontrol in concrete construction. After secondary loading, the maximum strain of the support bar is only 47. 3 με, and thestress level is low, which is in elastic working state. The formwork support structure system meets the index requirements ofhigh precision construction accuracy of large fair⁃faced concrete tunnel engineering, and can be used for field construction.

Keywords:fair⁃faced concrete tunnel; steel formwork support system; high precision construction; in⁃situ load test

∗国家自然科学基金项目(51808466),四川省科技厅科研院所科技成果转化项目(2021JDZH0036),西南科技大学实验技术研究项目(17syjs⁃06).

第一作者:褚云朋,博士,教授,硕士生导师,主要从事结构抗震及加固改造研究,Email:chuyunpeng@ swust.edu.cn.

[引用本文] 褚云朋,钟燕,孙鑫晖,等. 大型混凝土洞体钢模板支撑结构承载性能试验研究[ J]. 建筑结构,2022,52(8): 99⁃104. CHU Yunpeng, ZHONG Yan, SUN Xinhui, et al. Experimental study on bearing capacity of steelformwork support structure in large concrete tunnel[J]. Building Structure,2022,52(8): 99⁃104.