  In this work, we propose a framework that constructs reduced order models for
nonlinear structural mechanics in a nonintrusive fashion, and can handle large
scale simulations. We identify three steps that are carried out separately in
time, and possibly on different devices: (i) the production of high-fidelity
solutions by a commercial software, (ii) the offline stage of the model
reduction and (iii) the online stage where the reduced order model is
exploited. The nonintrusivity assumes that only the displacement field solution
is known, and relies on operations on simulation data during the offline phase
by using an in-house code. The compatibility with a new commercial code only
needs the implementation of a routine converting the mesh and result format
into our in-house data format. The nonintrusive capabilities of the framework
are demonstrated on numerical experiments using commercial versions of the
finite element softwares Zset and Ansys Mechanical. The nonlinear constitutive
equations are evaluated by using the same external plugins as for Zset or Ansys
Mechanical. The large scale simulations are handled using domain decomposition
and parallel computing with distributed memory. The features and performances
of the framework are evaluated on two numerical applications involving
elastoviscoplastic materials: the second one involves a model of high-pressure
blade, where the framework is used to extrapolate cyclic loadings in 6.5 hours,
whereas the reference high-fidelity computation would take 9.5 days.
