Study of masonry arch bridge limit states with acoustic emissiontechniques

摘要

Masonry arch bridges form over 40% of the European bridge stock, 60% ofrnwhich are over 100 years old. With regards to the significantly increasing levels of loading andrnvolumes of traffic, establishing the safe limits of loading are becoming more and more urgent.rnDetermining the life expectancy of masonry arch bridges is necessary for managing the agingrnbridge stock. Acoustic emission is increasingly widely used for monitoring concrete andrnmetallic bridges, its application for masonry bridges is however currently very limited. Duringrnan extended series of large-scale laboratory masonry arch tests the use of acoustic emissionrntechnique has been investigating at the University of Salford, UK.rnThe ultimate and serviceability limit states for masonry arch bridges was investigated with thernuse of acoustic emission techniques. Crack propagation load was identified as the serviceabilityrnlimit state and was found to be as low as 30% of the ultimate limit state. Acoustic emission isrncapable of identifying residual damage occurring to the arch under long-term fatigue loadingrnand can warn of imminent damage. The technique can also be used for arches in poor conditionrnand shows great potential for condition assessment and monitoring of masonry arch bridges inrnthe traffic network.