浅覆大断面隧道长大管棚超前支护受力研究  

Research on forepoling force of long and large pipe roof for shallow tunnel large section under existing highway

作　　者：耿大新[1] 石钰锋[1,2] 阳军生[3] 杨峰[3] 

机构地区：[1]华东交通大学土木建筑学院,江西南昌330013 [2]江西省水利科学研究院,江西南昌330029 [3]中南大学土木工程学院,湖南长沙410075

出　　处：《华中科技大学学报（自然科学版）》2016年第6期98-103,共6页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：江西省博士后科研项目(2015KY07);江西省交通厅科研项目(2011H0019);华东交通大学博士科研启动基金资助项目

摘　　要：湘桂线石头岗隧道下穿衡昆高速工程,在对85m超长Φ159m大管棚内力现场测试分析基础上,建立精细化的数值模型对长管棚作用机理进行研究.提出管棚预支护结构受力的纵向可按掌子面前方受拉段、掌子面后方受压段、靠近洞口受拉段分为Ⅰ,Ⅱ,Ⅲ区,其中:Ⅰ区呈凸起分布,峰值位于掌子面前方一定距离处;Ⅱ区为凹形分布,计算峰值位置滞后掌子面一定距离;Ⅲ区自洞口向内呈逐步减小趋势,峰值位于洞口处.各区间长度除Ⅰ区维持基本不变外,Ⅱ和Ⅲ区间长度随掌子面掘进而增长;各区内管棚受力也随隧道掘进而增长,且表现为先快后慢趋势.Based on internal force test of the 85 m long φ159 m big pipe roof, a series of research on mechanism of big pipe roof was made on Shitougang Tunnel, which located in Xiang-Gui Line and un- derpass Heng-Kun expressway project. A three dimensional numerical model was carried out to inves- tigate the mechanical performance of the long and larger pipe roof. The results show that, in longitu- dinal direction, the stress of pipe roof can be classified Ⅰ , Ⅱ , Ⅲ region based on tension section a- head of the tunnel face, compressive section behind the tunnel face, and tension section near the en trance casing arch. I section presents a concave distribution shape, and peak value appears at a dis- tance in front of the excavation face; ]I section is in convex distribution, and the calculated peak lags tunnel face at a distance; Ⅲ section is in decreasing distribution shape, and the peak is located at the tunnel entrance. Regarding to region length, except I section maintains substantially unchanged, both length of Ⅱ and Ⅱsection increase with tunnel excavation. The pipe stress in all regions also have an increasing tendency, and fall into a regular slow after the first fast pattern.

关 键 词：隧道 下穿高速 长大管棚 现场测试 数值分析 

分 类 号：TU921[建筑科学—建筑设计及理论]