Plastic Strain Energy Based Damage Indices for Concrete Structures

This study proposes two indices for the damage evaluation of concrete structures.One is for concrete in compression and the other reflects the yielding and plasticization of steel. Both indices are calculated based on the plastic strain energy and represent the degree of damage of concrete and steel respectively. To investigate the applicability of the proposed damage indices, nonlinear finite element analyses were conducted for several types of reinforced concrete members and a steel-embedded concrete column specimen subjected to monotonic or reversed cyclic loading. Results show that the damage index of steel is almost 1.0 when the specimen reaches its yielding load and the damage index of concrete is almost 1.0 when the specimen reaches its maximum load or temporary load drop point