Addition of Partial-Depth Link Slabs to Bridge Structures: Role of Support Conditions

Abstract

Due to the maintenance and repair needs that commonly originate from expansion joints, link slabs are considered as a potential solution to move toward jointless bridges. The addition of partial-depth link slabs to existing bridges, however, can change the loading demand on not only superstructure components but also supporting piers. In particular, the consequences of adding link slabs to a bridge structure can vary, depending on support conditions underneath the individual link slabs. In the absence of any holistic study on this critical subject, the current study explored the effects of support conditions on strains and stresses developed in partial-depth link slabs through a full-scale laboratory investigation. For this purpose, various roller and pinned support conditions were tested and key response measures were recorded. The experimental tests were supplemented with finite-element simulations to further understand the effects of support conditions, taking into account various design details. The study was then extended to a representative bridge with the goal of evaluating how the addition of link slabs influences the loading demand that the bridge substructure experiences. Specifically, the effects of support conditions underneath the individual link slabs were modeled and evaluated. This provided original information about the change of loading demand that must be taken into consideration throughout the entire bridge structure when link slabs are considered to replace existing expansion joints.