Resilient connection for accelerated bridge constructions

Abstract

Resilience in bridges is of paramount importance as bridges are important transport assets that maintain mobility after disasters. The most common cause of extreme stress development on structures and especially bridges is dynamic loads due to floods, earthquakes, strong winds, truck and ship collisions. In the international literature, there an ongoing research in support of adaptable and low-damage bridge connections for bridges and structures exposed to dynamic loads. This paper focuses on the design and assessment of a novel connection based on extensive numerical modelling of a 3D Finite Element (FE) model of the connections developed in Abaqus. The connection, which is essentially a resilient hinge, connects the foundation with the bridge pier and the latter with the deck, which are the positions where typically RC hinges are formed during extreme dynamic loads, e.g. earthquakes. A similar connection was designed before, however, this paper offers a design methodology and advances the connection by providing improvements to its mechanical characteristics, i.e. the geometry, resolving issues with regard to stress concentration by improving the contact surface geometry, the consideration of the friction and the optimization of its components. The paper concludes with a discussion on the connection constructability, therefore enabling further applications of the proposed design. The results also demonstrate that even though the rebars of the hinge undergo excessive elongation, the connection maintains a significant bending moment capacity, therefore not hindering the integrity of the bridge. Moreover, it is observed that the compressive zone of the hinge remains intact, thanks to the high strength of the steel, therefore no shortening of the RC column is expected.