Cohesive Element Model For Numerical Simulation Of Fracture In Concrete

Numerical simulation of concrete fracture is a challenging topic. Concrete crack has in important effect on concrete structure, so it is critical to the calculation of concrete crack properly, especially in dynamic problem. Cohesive element model is regarded as an effective tool to solve the fracture calculation. In the cohesive theory, fracture is regarded as a gradual process in which the separation of the incipient crack flanks is resisted by cohesive tractions. The relation between the cohesive tractions and the opening displacements is governed by a cohesive law. Cohesive models furnish a complete theory of fracture that is not limited by any consideration of material behavior, finite kinematics, non-proportional loading, dynamics, or the geometry of the specimen. The cohesive theory has proved effective in the simulation of complex fracture processes including: the fragmentation of brittle materials; dynamic fracture and fragmentation of ductile materials; and the dynamic Brazilian test for concrete.In this paper the introduction of the use cohesive element in concrete structure is given, and a kind of 2-D isoperimetric cohesive element is deduced. The fracture process of concrete notch beam is calculated by Fortran programming. The result shows that the method is feasible.