Analytical Solution for Cohesive Layer Model and Model Verification

The objective of this work was to find an analytical solution to the stresses in the cohesive damage zone and the damage zone length at the interface between a fibre reinforced polymer (FRP) plate and concrete substrate. Analytical solutions have been derived to predict the stress in the cohesive layer when considering the deformation in the stiff substrate. A two-dimensional cohesive layer constitutive model with a prescribed traction-separation (stress-strain) law was constructed using a modified Williams' approach, and analytical solutions derived for the elastic zone as well as the damage zone. Detailed benchmark comparisons of analytical results with finite element predictions for a double cantilever beam specimen were performed for model verification, and issues related to cohesive layer thickness were investigated. It was observed that the assumption of a rigid substrate in analytical modelling can lead to inaccurate analytical prediction of the cohesive damage zone length.