A consistent characteristic length for smeared cracking models

Abstract

A numerical scheme for crack modelling by means of continuous displacement fields is presented. In twodimensional problems a crack is modelled as a limiting case of two singular lines (with continuous displaccnients, but discontinuous displacement gradients across them) which tend to coincide with each other. An analysis of the energy dissipated inside the band bounded by both lines allows one to obtain an expression for the characteristic length as the ratio between the energy dissipated per unit surface area (fracture energy) and the energy dissipated per unit volume (specific energy) at a point. The application of these mathematical expressions to the finite element discretized medium allow one to obtain a general spatial and directional expression for the characteristic length which guarantees the objectivity of the results with respect to the size of the finite element mesh. The numerical results presented show the reliability of the proposed expressions.

Regularization of first order computational homogenization for multiscale analysis of masonry structures

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A Tow-Level Progressive Damage for Simulating Carbon-Fiber Textile Composites: Interim Report

“…The present damage model is regularized to generate mesh independent results using the approach developed by Oliver (1989) and Hillerborg (1976). The approach assumes that a single crack forms in an element for each damage mode.…”

Computational modeling of high performance steel fiber reinforced concrete using a micromorphic approach

“…We reach this objective by introducing a model 640 characteristic length related to the finite element mesh size 641 and the fracture energy of the component. Thus, the soft-642 ening modulus H m in Table 1 Table 1 and 646 h e is a representative finite element size consistent with the 647 crack orientation (see additional details in [13]). …”