沉管隧道垫层作用机理离心试验研究  

Centrifugal modeling experimental study on cushion mechanism of immersed tube tunnel

作　　者：岳夏冰[1] 谢永利[1] 张宏光[1] 胡指南[1] 

机构地区：[1]长安大学公路学院,西安710064

出　　处：《工程勘察》2013年第8期11-14,共4页Geotechnical Investigation & Surveying

基　　金：国家科技支撑计划(2011BAG07B00);中央高校基金(CHD2012TD009)

摘　　要：以港珠澳沉管隧道天然地基段某一横断面为研究对象,通过离心试验模拟了沉管隧道不同垫层厚度工况下施工的整个过程,揭示了沉管隧道中垫层、沉管及地基相互作用的机理,探讨垫层在沉管隧道中的作用,为沉管隧道的设计施工提供依据。结果表明,垫层通过侧向挤密变形,协调了沉管与垫层、垫层与地基之间的变形,减小了沉管的应变,均化了沉管应变分布及基底应力分布,减小了应力集中现象,使得基底竖向反力均匀程度提高;设置合理的垫层厚度既减小了不均匀沉降,对工后沉降量也能有一定程度的减小。Taking certain cross section of the natural foundation in the Hong Kong-Zhuhai-Macao immersed tube tunnel as study object, the centrifugal model tests of the whole construction process with different cushion layer thickness are carried out. The interaction mechanism of the cushions, the immersed tube and the foundation in the immersed tube tunnel is revealed. The role of the cushion layer in immersed tube tunnel is explored. The results show that the deformations between the immersed tube and the cushion layer, the cushion layer and the foundation are coordinated through the lateral compacting deformation of the cushion layer. The strain of the immersed tube is reduced, and the distributions of the immersed tube strain and basement stress are homogenized. The phenomenon of stress concentration is reduced so that the uniformity of the basement vertical reaction is improved. The reasonable thickness of the cushion layer can not only reduce the uneven settlement, but also can make the settlement after construction have certain degree of decrease.

关 键 词：沉管隧道 离心模型试验 垫层 基底应力 沉管应变 

分 类 号：TU411.93[建筑科学—岩土工程]