Damage identification of simply support beam based on strain energy information entropy

Concrete simply support beam is widely used in small and medium-sized bridges. As the main load-carrying members of bridge, hinged slabs and joints are easy to be damaged in service. In this paper, based on the superiority with high sensitivity and strong anti-noise of strain energy to damage, a strain energy information entropy index is proposed here for identification of local damage of hinge joints and hinged slabs, and a new damage index of local strain energy entropy function is constructed according to the strain energy of hinge joint element and its surrounding element. A simply support beam is establishment to verify the effectiveness of the proposed index. Numerical simulation results show that the damage index of hinge joints can accurately locate and quantify the damage degree of single hinge joint and multiple hinge joints. The improved modal strain energy information entropy index is sensitive to single hinged slab damage and can accurately identify damage at 5% and 10% noise levels.