Dynamic response of a cracked multi-span continuous beam subjected to a moving multi-axle vehicle load

Truong-Son Pham (1) , Tien Hoang (1) , Denis Duhamel (1) , Gilles Forêt (1) , Franziska Schmidt (2) , François-Baptiste Cartiaux (3) , Véronique Le Corvec (3)

1 ENPC - École des Ponts ParisTech
2 Université Gustave Eiffel
3 OSMOS GROUP [Paris]

An analytical model is developed to calculate the dynamic response of a cracked multi-span continuous beam, subjected to a multiple-axle vehicle load. In this model, the vehicle load is considered as a series of concentrated moving loads at a constant velocity. Meanwhile, the crack is modelled by a spiral spring. Thereafter, the cracked span is considered as a two-span beam, connected by the spring at the position of the crack. By using the Euler-Bernoulli beam theory, the relations between the two successive spans can be obtained from the boundary conditions at the supports and the position of the crack. This technique makes it possible to calculate the eigenmodes of the beam. The response of the beam is finally obtained by the superposition of the modes. This model allows us to quickly analyze the influence of the cracks (depth, location) and of the vehicle (loads, velocity) on the response. Moreover, this model is validated by finite element modelling and some numerical results are given.

Mots clés: Multi-span continuous beam; Cracked structure; Moving loads; Transfer Matrix Method

Domaines: Matériaux et structures en mécanique [physics.class-ph]

Truong-Son Pham, Tien Hoang, Denis Duhamel, Gilles Forêt, Franziska Schmidt, et al.. Dynamic response of a cracked multi-span continuous beam subjected to a moving multi-axle vehicle load. International Conference on Structural Health Monitoring of Intelligent Infrastructure, Jun 2021, Porto, Portugal. ⟨hal-03689440⟩