大断面黄土隧道仰拱受力及变形规律研究  

Research on Stress and Deformation Rules of Inverted Arch for Large Section Loess Tunnel

作　　者：樊纯坛 梁庆国[2] 丁冬冬 FAN Chun-tan;LIANG Qing-guo;DING Dong-dong(Department of Civil Engineering,Shandong Polytechnic,Jinan 250104 ,China;Schoo of Civil Engineering,Lanzhou JiaotongUniversity,Lanzhou 730070,China;China Railway Lanzhou Bureau Group Co. Ltd.,Lanzhou 730070,China)

机构地区：[1]山东职业学院铁道工程与土木工程系,济南市250104 [2]兰州交通大学土木工程学院,兰州市730070 [3]中国铁路兰州局集团有限公司,兰州市730070

出　　处：《公路》2019年第3期315-322,共8页Highway

基　　金：国家自然科学基金项目;项目编号41562013;兰州交通大学百名青年优秀人才培养计划项目

摘　　要：为了研究大断面黄土隧道在受压时,仰拱的受力特性与变形规律,本文分别采用现场实测与室内模型试验两种研究方法,来监测隧道仰拱与仰拱模型的应力、应变与位移,并对监测数据进行归一化对比分析。研究结果表明:隧道围岩压力在仰拱部分的分布呈现"两头大,中间小"的形状;隧道仰拱处的钢拱架两边受压,中间受拉,而仰拱混凝土应变全为压应变,其中仰拱拱底的混凝土压应变最小;仰拱模型破坏时围岩压力以压应力为主,两仰拱拱脚部分的压应变最大,且仰拱拱底出现了拉应变,说明仰拱拱底开裂是受拉破坏处;仰拱受压时左右仰拱拱脚会产生弯矩,同时仰拱拱底也会产生弯矩,使得仰拱拱底的压应变逐渐转变为拉应变。In order to study the stress characteristics and deformation rules of inverted arch in large section loess tunnel under compression,two methods of field measurement and indoor model test are used in this paper so as to monitor the stress strain and displacement of the tunnel invert and invert models and the normalized data are compared and analyzed.The results show that:the distribution of surrounding rock pressure in the invert part of the tunnel presents the shape of "big at both ends and small in middle";the steel arch at the invert of the tunnel is compressed on both sides and tensioned in the middle,the strain of invert concrete is compressive strain,the compressive strain of concrete at the bottom of invert arch is minimum;compressive stress is the main pressure force of surrounding rock during the failure of invert model,and the compressive strain of the arch foot is the largest,and the tension strain appears at the bottom of the inverted arch,it is indicated that the cracking of invert arch is the place under tension;when the inverted arch is compressed,the right and left invert arches produce moment,at the same time,the bottom of the inverted arch also produces bending moment,so that the pressure strain at the bottom of the inverted arch is gradually changed into the tensile strain.

关 键 词：黄土隧道 隧道仰拱 模型试验 围岩压力 归一化 研究 

分 类 号：U455.49[建筑科学—桥梁与隧道工程]