管幕-箱涵顶进法在南水北调穿越工程中的应用

Application of pipe screen-box culvert jack-in method in South-to-North Water Transfer Crossing Project

管幕-箱涵顶进法,采用泥水平衡顶管机顶进钢管幕,先用顶管法在预顶箱涵位置的周围顶进若干根钢管,靠各钢管间的锁口将钢管咬合在一起形成封闭的钢管幕,再在该钢管幕的围护下顶进预制好的钢筋混凝土箱涵。此方法施工简单、精度高,进度和质量易于控制,在天津干线输水工程中应用效果良好。本文叙述了该方法的施工要领,提出了顶进精度的控制措施。

Slurry balance pipe jacking system is adopted for jacking the steel pipe screen in pipe screen-box culvert jack-in method. Jack-in method is firstly used for jacking several steel pipes around the position of pre-jacked box culvert. Steel pipes are locked together for forming sealed steel pipe screen by locking notch close to all steel pipes. Then,the pre-cast reinforced concrete box culverts should be jacked under the containment of the steel pipe screen. The method is characterized by simple construction,high precision and easy control of progress and quality. It has good application effect in Tianjin main line water diversion project. In the paper,construction keys of the method are described,and control measures of jack-in precision are proposed.