Toolbox with Nondestructive Testing Methods for Condition Assessment of Railway Bridges

Abstract

The unified economic structure of the European market requires a unified transport infrastructure to ensure seamless and barrier-free transportation of passengers and goods. The European Commission has been funding the European Integrated Project, Sustainable Bridges, to comply with future traffic demands. The main objective of the project is to assess reliably and upgrade the bridge infrastructure for the required increase of axle loads and transport volume. Thirty-two institutes from 12 countries have developed unified procedures for the assessment and improvement of the existing railway bridge stock under the guidance and review of six major European railway companies. Nondestructive testing (NDT) has been given a high priority. One of the work packages concentrates on the potential of advanced NDT methods and creates a toolbox with advisable methods for the condition assessment of all types of railway bridges. Although NDT methods are implemented in the quality assurance process in many industries, their application in the railway infrastructure is not common. Only a few countries have included selected NDT methods in their advanced condition assessment procedures for the management of their bridge stock. This paper describes current activities to enhance pulse-phase thermography, impulse radar, and acoustic methods. The advanced methods enable infrastructure owners to verify construction plans; assess structures, repair, and strengthening quality; or identify in-service damages. An automated scanning system for combined acoustic and electromagnetic measurements has been developed recently. The results can be combined through data fusion techniques to increase their value for the bridge owners.