Experimental and numerical assessment of scoured bridges with protective bonded steel plates against vessel impact

Abstract

Water-crossing bridges are exposed to two threats in their service life – local scour and vessel impact. However, knowledge gaps exist towards understanding the behavior of water-crossing bridges when protected to resist such dual hazards, for instance, using bonded steel plates in bridge piers. Significant challenges are posed by modeling the nonlinear process of a complex vessel-bridge impact system under variable scour conditions. In this work, pendulum impact tests were conducted to simulate this process using ten scaled bridge pier-foundation system models with artificially introduced scour conditions. Based on the test results, an explicit finite-element (FE) program was developed to verify the material models, which were further adopted to develop the FE models for simulating a full-scale three-span steel-reinforced concrete bridge. The numerical vulnerability results reveal that the nominal damaging-impact velocity (NDIV) that leads to local structural damage in the bridge pier decreases as the scour depth increases. This paper further investigates the benefit of using bonded steel plates as a countermeasure against barge impact. Numerical results indicate that bonded steel plates can effectively reduce the local damage of the bridge pier under damaging NDIVs and various scour conditions.