Bridges

This paper presents the most recent research progress on an innovative bridge column joint, aimed at achieving low-damage seismic bridge design. Ductile design has been widely used for the design of bridge sub-structures, as an economic and efficient design philosophy. Plastic hinges are allowed to form at the Damage Control Limit State (DCLS) to provide displacement ductility to structures. However, repairing seismic-induced damage in bridge structures and understanding their residual capacity after major earthquake events has proven challenging.

The research aims to develop an easy-to-adopt hinge joint with flag-shaped hysteresis systems to provide damping for bridge structures and achieve a damage-free state even up to the Collapse Avoidance Limit State (CALS) events. The proposed joint consists of Resilient Slip Friction Joints (RSFJ), which provide compression and tension coupling and uplift capacities, and vertical rotational bearing for transferring the vertical loads.

A series of non-linear static analysis and Time-History analysis have been conducted to evaluate the performance of the proposed joint under different level of seismicity. The Ductile Self-centring Joints (DSJs) have been modelled as a combination of “Damper-Friction Spring” links and translational fixed link to the pile top below the capping beam to replace the pile top hinges.

This paper provides an overview of the current development and the potential applications of the DSJ for bridge structures. The paper will include an example design of a DSJ bridge sub-structure to demonstrate the advantages of this joint.