Experimental and simulation study on seismic resilience in bridge piers affected by saline soil corrosion

Abstract

By simulating a salt-laden soil corrosion environment, immersion corrosion tests on concrete specimens, rust tests on rebar, and regional immersion corrosion tests on bridge piers were conducted. The objective was to study the variations in the seismic performance of bridge piers across different corrosion cycles. In this study, four bridge piers underwent pseudo-static loading tests, three of which were subjected to corrosion, with the longitudinal rebar experiencing a maximum corrosion rate of 16.81 %. The OpenSees finite element platform was utilized to conduct simulated analyses of the bridge piers across different corrosion cycles, incorporating the mechanical performance test results of the corroded rebar and concrete after immersion. The findings suggest that the corrosion rate of the longitudinal rebar in the bridge piers throughout the same corrosion cycle did not deviate by more than 15 % from the results of the rebar rust tests. Differences in peak load under the same corrosion cycle between the experimental data and the numerical simulation results were no more than 7.7 %, which is considered an acceptable level of agreement. According to the simulation results, when the longitudinal reinforcement corrosion rate is less than 6.69 %, the corroded bridge piers have an initial stiffness that is 48.2 % higher than the uncorroded columns. However, as the corrosion rate continues to increase, the reinforcing effect of changes in concrete strength on initial stiffness diminishes due to the development of cracks in the protective layer. This finding is also supported by quasi-static experiments. To summarize, the seismic performance of the bridge piers declines as the corrosion cycle lengthens, showing a faster loss in the later phases compared to the uncorroded columns.