Numerical investigation of wear processes by a gradient‐enhanced damage‐plasticity model

The prediction of failure mechanism in structures are always an important topic in the field of computational mechanics. Finite element computations of an inelastic material involving softening behavior (e.g. softening plasticity or damage) can suffer from strongly mesh‐dependent results. Therefore, such continuum models should be equipped with a regularization (localization limiter) strategy to overcome the above‐mentioned problem. In this study, we present a framework for gradient‐enhancement for coupled damage‐plasticity material model derived by means of Hamilton's principle for non‐conservative continua. This model is applied for the numerical investigation of wear processes as they occur, e.g. in the case of mechanized tunneling. These investigations require a fine resolution of the involved constituents (cut sheet and abrasive particles in the soil). Consequently, a numerical strategy for the damage‐plasticity model is demanded that allows for time‐efficient simulations. In this paper, we present a first step to the mentioned ultimate goal. To this end, a numerical framework for gradient‐enhanced damage‐plasticity coupling is proposed that is based on a combination of the finite element method with strategies from meshless methods. We demonstrate that this framework keeps the computational effort limited and for each load step close to the purely elastic problems. Several numerical examples prove the elimination of the pathological mesh dependency of the results. Furthermore, first results to the simulation of wear in tunneling machines are presented.