海口市侨中路隧道设计关键技术分析

Analysis of Key Technologies for Design of Qiaozhong Road Tunnel in Haikou

研究目的:海口市侨中路隧道工程具有外部环境复杂、工期紧张、结构埋深浅等特点,根据工程特点和工期要求确定了盖挖顺作的施工方法。本文结合该工程,研究盖挖顺作法隧道中常用的三种立柱——钢格构立柱、钢管混凝土立柱和钢筋混凝土钻孔灌注桩立柱的特点、计算方法和适用性。研究结论:(1)基于该工程特殊的工期要求、浅埋层地质条件和基坑深度,确立了盖挖顺作的施工方法;(2)钢格构立柱、钢管混凝土立柱和钢筋混凝土钻孔灌注桩立柱型式均可应用于该隧道工程,钢格构立柱具有施工和底板防水处理简单且造价低的优势,但竖向承载能力相对较差;(3)钢管混凝土立柱具有承载能力高、底板防水处理简单但施工精度要求高的特点;(4)钻孔灌注桩立柱具有承载能力高、施工简单的特点,但底板防水处理困难;(5)根据本工程实际情况和施工工艺水平选定了钢管混凝土立柱;(6)相关结论可应用于采用盖挖顺作法施工的地下工程领域。

Research purposes： The project of the Qiaozhong Road Tunnel in Haikou had the features of complex external environment, tight construction duration and shallow structure etc. According to the project features and the requirement of construction process, the cover - excavation consequent method was used. Combined with this project, the study was done on the characteristics, calculation methods and usability of the three types of columns - steel lattice column, concrete filled steel tube column and reinforced concrete bored pile column. They are commonly used when the cover- excavation consequent method is adopted. Research conclusions： （ 1 ） According to the special demands of the tight construction duration, the geological conditions of shallow buried stratum and depth of foundation pit, the cover - excavation consequent method was used for this project. （2）The steel lattice column, concrete filled steel tube column and reinforced concrete bored pile column were suitable for this tunnel project. The steel lattice column had the features of simple construction and easy waterproofing treatment for floor plate and low cost, but the vertical bearing capacity was relatively poor. （3）The concrete filled steel tube column had the features of the good bearing capacity and simple waterproofing treatment, but it required the high construction accuracy. （4） The reinforced concrete bored pile column had the features of the good bearing capacity and simple construction, but the waterproofing treatment was complex. （5）According to specific engineering conditions and construction technology level, the concrete filled steel tube column was used for this project. （6）The conclusions could be applied in the underground engineering with the cover- excavation consequent method.