To analyze the influence of concrete damage on FRP confined concrete

264 test data was collected from published literature

and a large database was established

which contains cross-sectional shapes

damage types

and damage levels of specimens

and FRP confined stiffness. Based on the database

the existing lateral strain-axial strain relationship models were evaluated

and a new lateral strain-axial strain relationship model of FRP confined pre-damage concrete columns was established by modifying Jiang’s model. Results show that Jiang’s model could accurately describe the lateral strain-axial strain behavior of FRP confined undamaged circular concrete columns

but the existing models were not suitable for FRP confined damage concrete columns. With the increase of concrete damage level

the deviation between the calculated value and the test value of the existing models increased. The proposed model was verified by database and could predict the lateral strain-axial strain behavior of FRP confined damage concrete column with good accuracy

which can be applied to FRP confined high temperature damage concrete columns. The model in this paper can be used for FRP confined pre-damage circular

square

and rectangular concrete columns as well as for the calculation of FRP confined preloading concrete columns and square columns.