Simplified nonorthogonal crack model for concrete

A new material model that accounts for fracture of concrete is presented. The model is based on the crack-band concept, providing a formulation suitable for application in the nalysis of reinforced concrete structures. The material model features simplified representations of both nonorthogonal cracking and the influence of this cracking on local material stiffnesses. At an integration point, only one primary crack of fixed direction and one rotating crack are allowed to develop. Although the cracks are nonorthogonal to a varying degree during loading their effect is assessed approximately on softening moduli in orthogonal directions and thus coupling effects are accounted for simply. Numerical examples show the satisfactory performance of this pseudo-nonorthogonal fracture model