A new continuous-discontinuous damage model: Cohesive cracks via an accurate energy-transfer process

作者：Tamayo Mas Elena; Rodriguez Ferran Antonio^*

来源：Theoretical and Applied Fracture Mechanics, 2014, 69: 90-101.

DOI：10.1016/j.tafmec.2013.11.009

• Continuous-discontinuous strategy
• Regularisation
• Smoothed displacements
• Cohesive cracks
• Energy balance

A new continuous-discontinuous strategy to describe failure of quasi-brittle materials is presented. For the early stages of the failure process, a gradient-enhanced model based on smoothed displacements is employed. As soon as the damage parameter exceeds a critical value D-crit %26lt; 1, a cohesive crack is introduced. A new criterion to estimate the energy not yet dissipated by the bulk when switching models from continuous to continuous-discontinuous is proposed. Then, this energy is transferred to the cohesive crack thus ensuring that the continuous and the continuous-discontinuous strategies are energetically equivalent. Compared to other existing techniques, this new strategy accounts for the different unloading branches of damage models and thus, a more accurate estimation of the energy that has to be transferred is obtained. The performance of this technique is illustrated with one- and two-dimensional examples.

• 出版日期2014-2