Theoretical Analysis On Interfacial Stresses Of Plated Beam

Strengthening with bonded plates is one of the most widely used techniques for flexural upgrading of reinforced beams. It is a key issue that the interface debonding failure hinders the reinforcement effect. Based on elasticity theory, this paper derived theoretically differential equations of interfacial shear stresses and interfacial normal stresses, and accordingly analyzed the distribution features of interfacial stresses. Through the effect of plate thickness, plate modulus, adhesive layer thickness, adhesive layer modulus, the distance from the end of plate to support on interfacial stresses, analyzed the ways of improving interfacial stresses distribution.This paper attempts to a coupling method for the interfacial stresses. The coupling effect is created by the curvature mismatch between beam and bonded plate, which results from a fact that the elastic deformation of adhesive layer. The contribution of curvature mismatch to interfacial stresses was analyzed. On the basis of curvature mismatch between beam and bonded plate, this paper further derived theoretically differential equations of interfacial stresses which was incorporated shear deformations of the adherends in the axial plane that is perpendicular to the bonding interface, the shear deformation on the role of interfacial stresses was analyzed.Taking into account that the beams are often reinforced with bonded prestressed plate in actual project, this paper further derived theoretically differential equations of interfacial stresses under prestressing force. And non-prestressed and prestressed under different initial force distribution features of interfacial stresses were compared. The effect of plate thickness, plate modulus, adhesive layer thickness, adhesive layer modulus, the distance from the end of plate to support on interfacial stresses in a beam strengthened with bonded prestressed plate was analyzed.