Performance of Concrete-Filled Steel Tube Bridge Columns Subjected to Vehicle Collision

Abstract

Collision of vehicles into RC bridge columns can result in significant damage to individual bridge components, leading to partial or full collapse of the entire bridge. Among various alternatives to RC columns, concrete-filled steel tubes (CFSTs) have received growing attention because of their rapid construction, reduced labor requirement, and reasonable material cost. Despite the promise of this alternative, however, there is a gap in the existing literature concerning the measures that can be used for the analysis and design of this important category of bridge columns subjected to impact loads. To address this gap, a detailed investigation is conducted in the current study, using a set of impact simulations. For this purpose, representative finite-element (FE) models are developed and validated with the experimental test results. To make a direct comparison possible, the numerical simulations include both CFST and RC columns under a range of vehicle impact scenarios. The structural performance is evaluated using a comprehensive set of measures, including peak dynamic force (PDF) and equivalent static force (ESF). On establishing the necessary metrics, the current study provides a systematic effort to examine the contribution of the main analysis and design parameters to the impact response of the columns under consideration. Based on the simulation results, the sufficiency of the current specifications is evaluated, and a generalized equation is proposed to predict the ESF for CFST columns.