Newly-developed shear connectors for timber bridges

摘要

This paper describes an investigation into fabrication methods and structural performance of shear connectors used to induce composite action between timber bridge decking and timber log stringers. Composite action improves structural efficiency and produces a design concept with the potential for prefabrication and modularisation. Three shear connector configurations were investigated. In the first, shear connectors were grouted perpendicular to the stringer longitudinal axis; in the second, at 45°; and in the third, pairs of shear connectors were installed at 45° to the axis of loading and at 90° to each other. The structural response was investigated through a number of push-out tests involving loading and unloading cycles, and subsequently the test data generated were assumed to fit a load versus displacement relationship. The third configuration was adopted for future timber bridge construction because it yielded the highest shear transfer capacity and stiffness. A fabrication method was developed that overcame fabrication difficulties related to grout leakage from various sources.