Bridges

The bolted web splice-plates which connect the segments of steel I-girder or steel box-girder bridges commonly measure essentially the same height as the girder web, representing a single bolt group.

Less commonly, the bolted web splice-plates which connect the segments of steel I-girder or steel box-girder bridges are divided into multiple pieces to allow the passage of longitudinal web stiffeners, or to facilitate the method of construction. In cases such as these: the divided web splice-plates are shorter than the height of the girder web and reflect multiple bolt groups which behave differently and exhibit different load-resistances than those found for the single bolt group relevant to the web splice-plates which measure essentially the same height as the girder web. This paper reports numerical investigations of the bolted web-splice-plates of a typical Australian bridge, for the following alternative conditions:

1. The ‘full-height splice plate’ (FHSP) case, where the interior and exterior web splice-plates are identical and measure essentially the full height of the girder web, and
2. The ‘divided splice plate’ (DSP) case, where the exterior web splice-plate (including bolt pattern) is identical to the ‘FHSP’ case, however the interior web splice-plate is divided into three plates.

This paper investigates the different behaviours of the FHSP and DSP cases using hand calculations which adopt different hypothetical load-distribution models; bolt forces are contrasted to the predictions of finite element analysis, and the most-appropriate approach to splice plate design is recommended.