STRESSES IN SIMPLE SHEAR TEST SPECIMENS FOR STEEL OR FRP-TO-CONCRETE BOND STRENGTH: A 3D FINITE ELEMENT STUDY

摘要

One of the key factors affecting the behaviour and reliability of reinforced concrete structures strengthened with externally bonded steel plates or advanced fibre reinforced plastic (FRP) composites is the bond behaviour between the external plate and the concrete substrate. Extensive research has been carried out on external plate-to-concrete bond strength. Many different experimental set-ups have previously been used to determine bond strength. Because of the differences of width and the Poisson's ratio between the test plate and the concrete specimen as well as the details of test set-up, the true stress state in such a test structure is likely to be three-dimensional. However, this 3D nature of stress distribution is generally ignored in theoretical analysis by adopting the plane stress assumption. This paper presents a finite element analysis on the stress distributions in a typical test set-up. Results show that the stress distributions can be significantly different from plane stress assumption.