张卓航

摘  要：综合道路管廊是一個城市中集中铺设油气管道，光纤通信等基础设施的公共交通枢纽。管廊整体结构较长，穿越不同地质情况时很容易发生沉降差异，进而产生结构裂缝乃至彻底破坏。针对不同土质下道路管廊易出现不均匀沉降这一工程问题，依托益阳管廊项目，借助FLAC3D模拟软件建立有限元模型，探究了土体换填后管廊顶部管壁采用预应力锚索加固对沉降产生的作用。研究结果表明：在土体换填后，管廊顶部管壁采用预应力锚索加固可以有效地控制管廊沉降，随着对锚索施加预应力的增大，管廊周围土体沉降逐步减小。当锚索预应力达到一定阈值后，沉降量趋于稳定。在管廊中打入预应力锚索后，主要改变管廊周围的土体沉降，远处路基底部土体沉降略有增大。研究成果可供工程上综合道路管廊结构设计借鉴。

关键词：道路综合管廊  预应力锚索  FLAC3D  土体换填  沉降

中图分类号：TU990.3                       文献标识码：A                  文章编号：1674-098X（2021）01（a）-0007-03

Abstract：Road comprehensive pipe gallery is a kind of road comprehensive pipe gallery which is usually constructed together with urban roads. The structure of it is long， when the pipe gallery passes through different geological conditions， it is easy to occur settlement difference， which will lead to structural cracks and even complete destruction. Aiming at the problem that road pipe gallery is prone to uneven settlement under different soil materials， according to Yiyang pipe gallery project， the finite element model was established by using FLAC3D to explore the influence of prestressed anchor cable reinforcement on the settlement of pipe gallery top wall after soil filling. The experimental results show that the settlement of pipe gallery can be effectively controlled by using prestressed anchor cable to reinforce the top wall of pipe gallery after the soil is replaced. When the anchor cable prestress reaches a certain threshold， the settlement tends to be stable. The soil settlement around the pipe gallery is mainly changed after the prestressed anchor cable is put into the pipe gallery. The settlement at both ends of the subgrade increases slightly. The research results can be used for reference in the structural design of integrated road pipe gallery.

Key Words： Road comprehensive pipe gallery; Prestressed anchor cable; FLAC3D; Soil replacement;  Settlement

道路综合管廊作为城市地下管廊的主要结构型式，是建设智慧城市不可或缺的一类基础设施[1]。管廊主体结构较长，在外部荷载和软土地基条件下易产生沉降差异，进而导致管廊结构破坏，造成安全事故。目前处理软土地基的方案主要有：换填法[2]、振杆密实法[3]、置换法[4]、胶结法[5]、CFG桩法[6]等。李荣华、刘伟华等人提出了铺设土工布和土工格栅的方式分散管廊对土体的作用力，达到减小管廊沉降的效果[7]。周济龙，文前程等人分析了管背填土密实度等因素对管廊沉降的影响[8]。……