Experimental study on asynchronous construction for composite bridges with CSWs: Comparative study

Abstract

With the increase of bridge span and width, the traditional cantilever construction has disadvantages such as excessive weight, excessive steel consumption, high safety risk and poor economy, which severely restrict the development of a wide and large span composite girder bridge with corrugated steel webs (CSWs). This paper fully considers the structural characteristics of composite bridge with CSWs, and innovatively proposes a asynchronous construction method that uses the CSWs as the self-supporting members for supporting the construction loads, including the weight of the hanging basket and concrete. Compared with the traditional cantilever construction, the hanging basket is simplified to a simple working platform with a weight reduction of 50%, a height reduction of more than 90%, and the hanging basket is simplified from the cantilever system to a simple support system, which has the advantages of good stability and good safety, in addition, the construction work platforms is increased from 1 to 3 and the construction period reduced by 30%. Through the model tests of two double cantilever girders with CSWs, the mechanical characteristics of conventional cantilever pouring construction and asynchronous pouring construction of multi-cell single-box girder with CSWs are studied for the first time. The failure modes, shear behavior and linear shape of the main girder under the two construction methods are compared and analyzed. Based on the results of test and finite element models, the key components of the composite girder bridge with CSWs in asynchronous pouring construction are identified, and corresponding optimization suggestions are provided.