马蹄形隧道初期支护结构力学及变形性能足尺试验研究  

Full-scale Experimental Study on Mechanical and Deformation Properties of Initial Support Structure of Horseshoe Tunnel

作　　者：王亚威 赵修旺 朱毅 郭江龙 WANG Yawei;ZHAO Xiuwang;ZHU Yi;GUO Jianglong(China Railway Engineering Equipment Group Co,Ltd,Zhengzhou 450016)

机构地区：[1]中铁工程装备集团有限公司,郑州450016

出　　处：《现代隧道技术》2023年第1期186-194,共9页Modern Tunnelling Technology

基　　金：中铁工程装备集团有限公司科研项目(装备研合2019-14)。

摘　　要：针对马蹄形隧道初期支护结构,采用足尺试验,通过埋设传感器对结构内力、结构表面应变及变形进行监测,分析了钢拱架与喷射混凝土初期支护结构的承载能力和变形性能。研究结果表明:(1)在弹性阶段,支护结构各截面所受弯矩和轴力关于结构中性轴左右对称,对应的径向位移幅值较小。(2)在塑性阶段,随着外加荷载的增加,支护结构的弯矩和轴力快速增大;支护结构呈现“拱底外凸,拱腰内凹”的变形状态,且近似关于中性轴左右对称。(3)支护结构最终在右拱肩型钢连接处失效破坏,破坏位置处混凝土与型钢呈大范围剥离状态,裸露的型钢外凸发生弯折破坏,结构极限承载力约为设计荷载的1.32倍。In view of the initial support structure of the horseshoe tunnel, the bearing capacity and deformation performance of the steel arch and shotcrete initial support structure are analyzed by using full-scale tests and monitoring the internal force, structural surface strain and deformation of the structure by embedding sensors. The results show that:(1) In the elastic phase, the bending moment and axial force on each section of the support structure are symmetrical about the neutral axis of the structure, and the corresponding radial displacement amplitude is small.(2) In the plastic phase, with the increase of the applied load, the bending moment and axial force of the support structure increase rapidly. The support structure presents a deformation state of "convex arch bottom and concave arch waist", and is approximately symmetrical about the neutral axis.(3) The support structure finally failed at the right arch shoulder section steel connection. The concrete and section steel at the failure location were in a large range of peeling state, and the exposed section steel bulge was bent and damaged. The ultimate bearing capacity of the structure was about 1.32 times of the design load.

关 键 词：马蹄形隧道 初期支护 喷射混凝土 足尺试验 承载能力 变形性能 

分 类 号：U451[建筑科学—桥梁与隧道工程]