港珠澳大桥珠海连接线拱北隧道曲线管幕顶管测量和轨迹控制技术

摘要

Pipe curtain engineering is the most difficult underground excavation part of the Gongbei T unnel in Zhuhai Section in Hongkong-Zhuhai-M acao Bridge. T his part is within the specified port area. T he pipeline is 4 to 5 m beneath the ground. The average pipe curtain length is 257. 92 m,composed of 361 620 mm steel pipes. The line is within the combination of transition curve and circular curve. It has following properties: pipe group jacking and starting each other,short spacing,small curve radius,accurate controlling,small surface subsidence and sensitive environment. In this paper,traverse survey,well orientation,top pipe measurement,track control and accuracy assessment were introduced in details,and these can be used for other similar engineering works.%管幕工程是港珠澳大桥珠海连接线拱北隧道暗挖段难度最大的项目之一，工程下穿拱北口岸限定区域，埋深4～5 m，管幕平均长度257.92 m，由36根直径1620 mm的钢管组成。线路位于缓和曲线和圆曲线组成的复合曲线上，其特点是群管顶进、互为接收始发、间距小、曲线半径小、精度控制高、地表沉降小、周边环境敏感。本文对从导线测量、一井定向、顶管测量、轨迹控制到精度估算的技术要点做了详细介绍，可为类似工程提供借鉴。