Improving Train Speed in Existing Short-Span Reinforced Concrete Railway Bridges Using Ballasted Pavement Retrofitting Method
Abstract
The purpose of this study is to look into ways of increasing trains speed in a railway network. To this end, an elastic and resilient layer under ballast layer was used as a retrofitting process of existing short-span reinforced concrete railway bridges which are commonly used bridges in railway networks. A three-dimensional finite element model incorporating the bridge, train, and track was developed. The model includes the train-track interaction, using an elastic and resilient layer under ballast layer in two types of bridge bearing (rigid and elastic bearing) for bridge span lengths of 2, 4, 6, and 8 m. Field test results were employed to authenticate the model, focusing on the impact of escalating train velocity in diverse ballast layer and bridge bearing scenarios. The utilization of resilient layer under ballast layer was shown to reduce the maximum values of the bridge deck’s acceleration and vertical displacement up to 30% and 20%, respectively. Furthermore, it was discovered that the train wagon vehicle body’s vertical acceleration increased at 140 km/h and decreased at 200 km/h. The method proposed here not only improves the operation condition of existing railway bridges, but also save environment from a vast amount of end-of-life waste tires. © The Author(s), under exclusive licence to Shiraz University 2024.