Numerical modeling of continuous steel concrete composite girders considering cracking of concrete

Abstract

In continuous steel concrete composite (SCC) girders, the concrete deck is susceptible to cracking because of the negative bending moment, which leads to the redistribution of forces and increases in deformations. The general practice adopted while designing the continuous SCC girder is to ignore the concrete deck in negative moment region and assume the steel girder to resist the entire negative bending moment, which may lead to an uneconomical design. In this regard, a simplified numerical procedure has been proposed, considering concrete cracking effects by aptly modifying the cross-sectional properties of the concrete deck. For this purpose, two different cross-sectional modifiers have been presented. The proposed procedure also incorporates partial shear connection. The proposed simplified numerical procedure is advantageous in terms of flexibility, generality, and the easiness with which it can be adopted in design offices for routine designs of SCC girders. The experimental results available in the literature used to validate the results of the proposed procedure show good agreement. Further, the effectiveness of the proposed procedure is demonstrated with the help of a parametric study. It is observed that a considerable reduction in the negative moment on the steel girder and reduction in deformations of the SCC girder can be achieved by adopting the proposed procedure. An example is solved to illustrate the proposed procedure in the appendix.