Theoretical and computational modelling of fracture and damage
Computational modelling of damage and fracture in materials and structures is a main research field of the Centre. The primary challenge is to develop constitutive models, which describe damage and fracture processes accurately, and are independent of the numerical discretisation. Constitutive models based on damage mechanics, plasticity theory, and linear and non-linear fracture mechanics have been implemented in a wide range of continuum and discontinuum methods. In brittle fracture, configurational forces have been applied to drive fracture propagation. In quasi-brittle and ductile fracture, the widely used cohesive-surface approach has been extended to include phenomena like in-plane stretching and mass transport. As alternative to continuum methods, lattice models – a prototypical discontinuum method – have been extended to include mass transport. Contributions have also been made to the regularisation of plasticity and damage models at incipient failure, i.e. by non-local averaging, or by including strain gradients in the constitutive model.
The models have been applied to a variety of structures made of materials ranging from fibre-reinforced composites and concrete to bone and wood. Applications include understanding fracture processes and brittleness in heterogeneous materials, the interaction of mass transport and fracture, prediction of fracture induced size effects on strength and the modelling of dynamic fracture.