Shear Properties of Tapered Box Girders with Steel Trapezoidally Corrugated Webs Considering Resal Effect

Abstract

A study on the shear properties of tapered box girders with steel trapezoidally corrugated webs (STCWs) considering the Resal effect was carried out based on theoretical analysis, experimental testing, and numerical simulation. This study verifies the Resal effect in tapered box girders with STCWs, which is the dominant factor that contributes to the significant differences in mechanical properties between prismatic and tapered box girders with STCWs. This paper points out that it is too conservative to accept that STCWs carry the entire vertical shear force in tapered box girders because a considerable percentage of the shear force is resisted by the inclined concrete slabs, which cannot be ignored especially in regions of large bending moments. Through analysis of a linearly tapered cantilever box girder with a single vertical force acting at the unrestrained end, the study found that the average shear stress of the STCWs decreases from the unrestrained end to the cantilever’s supported end, which is different from the case of prismatic members. Also, it was found that the root section near the support is not the most unfavorable position for the shear design of STCWs. Accordingly, the traditional method and assumptions for determining the shear stress of a prismatic beam with STCWs will cause considerable errors when applied to tapered members. Thus, a simple and effective equation for determining the shear stress of tapered girders with STCWs is suggested that considers the Resal effect. The correctness of the proposed equation was verified by comparing the theoretical predictions with both experimental data and finite-element simulation.