南水北调输水箱涵下穿高速公路顶进施工及控制要点

Jacking Construction and Control Points of Box Culvert under Crossing the Expressway in the South-to-North Water Diversion Project

随着近年来我国基础建设的发展和顶进施工技术的日益成熟，顶进施工已被越来越多地应用于穿越铁路、机场、市政道路、高速公路以及城市轨道交通等建筑物的通道或立交工程中，顶进环境越来越复杂，顶进精度也渐趋严格。但是，顶进截面和顶进行程却越来越大，控制路面沉降和横向移位、开裂就成为工程技术人员不可回避的新问题。通过对南水北调中线一期工程天津干线输水箱涵下穿京深高速顶进施工工艺和方法分析，指出了在横截面大、覆土浅、顶进跨度大和精度要求高等不利情况下的施工重点、难点和预控过程中采取的有效措施。对日后类似工程建设的安全实施提供了借鉴，具有参考价值。

In recent years, the development of infrastructure construction and jacking construction technology has become more sophisticated. The jacking construction has been widely used in a channel or the overpass projects as crossing railway, airport, municipal roads, expressway and urban rail transit with more complex i aeking environment and stricter jacking precision. However, as the jacking section and jacking distance turn larger and longer, control of pavement settlement and lateral displacement of crack in projects become the problems the technicians cannot avoid. This article aims at the analysis on the jacking construction technology and method of water box culvert under crossing Beijing-Sbenzhen Expressway in the Tianjin Trunk of the Middle Route of the South-to-North Water Transfer Project,points out the construction keys, difficulties and pre-control measures in the larger cross section with shallow earth coverage, large-span jacking and high-precision, which has a reference value for the sirnilar projects＇ construction.