双洞八车道小净距隧道施工力学模型试验  

Model Test of Mechanical Behaviour of Eight-lane Twin Highway Tunnels with Small Spacing

作　　者：张恒[1] 陈寿根[1] 程芳卉[2] 

机构地区：[1]西南交通大学交通隧道工程教育部重点实验室,四川成都610031 [2]中铁第一勘察设计院集团有限公司,陕西西安710043

出　　处：《公路交通科技》2013年第2期83-89,共7页Journal of Highway and Transportation Research and Development

摘　　要：基于室内模型试验,对深圳市南坪快速II期双洞8车道小净距隧道施工中隧道变形分布规律、二衬开裂破坏规律、裂缝集中部位及不同净距条件下二衬的极限承载力变化规律进行了研究。研究结果表明:在不同净距条件下,洞周各部位变形大小的分布情况基本相同,拱顶>右拱肩>左拱肩>仰拱>拱脚;起拱线以上各部位,包括拱顶、左拱肩、右拱肩的变形量,位移随双洞净距的增大而减小;可将12 m(约0.5B)作为IV级围岩下的最小合理净距,净距对起拱线以下各部位变形的影响不明显;最终裂缝集中出现在两洞仰拱和拱脚处,仰拱处裂缝全部贯通,拱脚处裂缝较小,一般不继续发展;远离中柱侧的拱肩也有可能出现贯通裂缝。Based on the indoor model test, the deformation distribution pattern, the regularity of secondary lining crack damage, the crack concentration parts and the change regularity of ultimate bearing capacity of secondary lining with different spacings in the construction of an 8-lane twin highway tunnels with a small spacing on Shenzhen Nanping expressway （ stage lI） are studied. The research result shows that （ 1 ） with different spacings, the tunnel deformation distribution in each part of the tunnel is almost same, the deformation values in turns are： vault 〉 right spandrel 〉 left spandrel 〉 invert 〉 arch foot; （2） above the springing line, including the vault, the left spandrel and the right spandrel, the displacements decrease as the spacing increases; （3） 12 m （about 0.5B） can be taken as the smallest reasonable spacing in class IV surrounding rock, whose influence on the deformation of different parts under the springing line is not obvious; （4） the final cracks concentrate in the inverts and arches of the twin tunnel and the cracks in the inverts are penetrating ones, while the cracks in the arches are small and generally do not continue to develop, the spandrel away from the interior column side may occur penetrating cracks.

关 键 词：隧道工程 大断面隧道 模型试验 施工力学 小净距 

分 类 号：U456.3[建筑科学—桥梁与隧道工程]