Comprehensive Application of Construction Techniques for Segmental Precasting and Cantilever Assembling to Bridge Works

The 60-m span continuous box girders of Contract B6 of Shanghai Changjiang River Tunnel and Bridge Project were constructed by the new technique of segmental precasting and cantilever assembling.The segmental girders were precast with high precision in the full hydraulic formwork by the short line match method,transported on the water,vertically lifted to the bridge deck and horizontally delivered to the working spot on the deck.The deck-traveling overhead launching gantry that can adjust the segmental girders all-directionally was designed and used for the cantilever assembling,and the whole construction process of the assembling was calculated and monitored by the computer so that the geometric shape and construction quality of the assembled girders can be ensured.In this paper,the techniques for the segmental precasting,cantilever assembling,temporary fixity as well as the construction of the closure segments are elaborated.