test_chaboche.jl

# This file is a part of JuliaFEM.
# License is MIT: see https://github.com/JuliaFEM/Materials.jl/blob/master/LICENSE

using Test, Tensors
using DelimitedFiles

let path = joinpath("test_chaboche", "unitelement_results.rpt"),
    data = readdlm(path, Float64; skipstart=4),
    ts = data[:,1],
    s11_ = data[:,2],
    s12_ = data[:,3],
    s13_ = data[:,4],
    s22_ = data[:,5],
    s23_ = data[:,6],
    s33_ = data[:,7],
    e11_ = data[:,8],
    e12_ = data[:,9],
    e13_ = data[:,10],
    e22_ = data[:,11],
    e23_ = data[:,12],
    e33_ = data[:,13],
    strains = [[e11_[i], e22_[i], e33_[i], e23_[i], e13_[i], e12_[i]] for i in 1:length(ts)],
    parameters = ChabocheParameterState(E=200.0e3,
                                        nu=0.3,
                                        R0=100.0,
                                        Kn=100.0,
                                        nn=10.0,
                                        C1=10000.0,
                                        D1=100.0,
                                        C2=50000.0,
                                        D2=1000.0,
                                        Q=50.0,
                                        b=0.1),
    mat = Chaboche(parameters=parameters)

    s33s = [mat.variables.stress[3,3]]
    for i=2:length(ts)
        dtime = ts[i] - ts[i-1]
        dstrain = fromvoigt(Symm2{Float64}, strains[i] - strains[i-1]; offdiagscale=2.0)
        mat.ddrivers = ChabocheDriverState(time = dtime, strain = dstrain)
        integrate_material!(mat)
        update_material!(mat)
        push!(s33s, mat.variables.stress[3,3])
    end
    @test isapprox(s33s, s33_; rtol=0.05)
end