Performance of New-Type Curved Steel Bridge Railings Subjected to Heavy Truck Collisions

Abstract

Japanese specifications for railing design have introduced two new improvements in functions for railings since 2004. The first is to require a landscape-friendly appearance and the other is to take account of flow in the road user's view from bridges. The concern with these functions has led to changes in design with requirements for more slender forms of railing beams and posts. Current Japanese specifications for railing design are concerned only with straight railings. Some researchers and engineers suspect that curved railings are more dangerous. The purpose of this research is accordingly to contribute to the development of two new types of curved bridge steel railings satisfying the new functional requirements and also to verify the above suspicion. A full-scale test is the ideal methodology for this study but this test involves a considerable cost and effort. Thus a combination between partial experimental tests for the new types of posts and numerical analyses is relied on here to study the performance of the new-type steel curved bridge railings. The procedures followed are : (1) to study performances of new posts experimentally under static and collision conditions ; (2) to develop numerical analyses to study performances of straight railings ; and (3) to apply these analyses to instances of new-type posts in curved railings in order to obtain a comparison with straight ones. The LS-DYNA 3D is engine software used for the numerical analysis. Based on the results of the study, a design recommendation is proposed for new-type curved steel railings.