Multiscale quasicontinuum modelling of fibrous materials
Lars Beex (Cardiff University), Ron Peerlings (Eindhoven University of Technology), Marc Geers (Eindhoven University of Technology)
From Atomistics to Reality: Spanning Scales in Simulations and Experiments Symposium A
Tue 2:40 - 4:00
CIT 165
Lattice models are frequently used to investigate the mechanical behavior of fibrous materials; materials that consist of a discrete fiber/yarn network at mesoscale. A disadvantage of lattice models is the associated computational cost. Multiscale methods may be used to reduce the computational effort associated with these models. In this work, principles of the quasicontinuum (QC) method (Tadmor et al. 1996, Langmuir) are used to reduce the computational costs of largescale lattice computations for fibrous materials. The QC method combines the following three advantages for fibrous materials that are all not shared by other multiscale approaches: 1. local mechanisms at the mesoscale can directly be incorporated in fully resolved domains, 2. no coupling procedures at the internal interfaces between the fully resolved domains and homogenized domains need to be formulated and 3. no associated continuum model is required, which can be complex to construct if large fiber rotations are involved. The QC method has so far only been used for atomistic lattice models (with reversible interactions), but lattice models for fibrous materials are mostly irreversible. Therefore, a new QC framework has been developed based on the virtual-power-statement of a non-conservative lattice. This ensures that the energy deliverd to the lattice is either stored or dissipated. The virtual-power-based QC method has been applied to a lattice model with local dissipative mechanisms and one with non-local dissipative mechanisms.