Test 12B: 2D plane stress – uniaxial displacement, primary-secondary creep

This problem provides evidence that Abaqus can reproduce the result from the benchmark defined by NAFEMS and cited as the reference solution.

This page discusses:

ProductsAbaqus/Standard

Elements tested

CPS8R

Problem description



Material:

Young's modulus = 200 × 103 N/mm2, Poisson's ratio = 0.3, Creep law: ε = A1σn1t+ A2σn2tm, A1 = 10−16, A2 = 10−14, n1=n2 = 5.0, and m = 0.5.

Boundary conditions:

ux=0 on line AD, uy=0 at mid-point of line AD and ux=0.1 on line BC.

Reference solution

This is a test recommended by the National Agency for Finite Element Methods and Standards (U.K.): Test 12(b) from NAFEMS Publication Ref: R0027, “NAFEMS Fundamental Tests of Creep Behaviour,” June 1993.

σxx=( 6.25×10-10+8×10-9[ 0.01t+t])-14

Results and discussion

The results are shown in the following table. The values enclosed in parentheses are percentage differences with respect to the reference solution.

Abaqus Results
tσxx
0.00 200.00 (0.00%)
1.64 97.44 (−0.18%)
14.23 74.39 (−0.55%)
68.75 60.47 (−0.79%)
270.08 49.94 (−1.12%)
538.51 45.08 (−1.35%)



Remarks

The total creep time for this test is 1000 hours. The times listed in the above table are the times calculated by the Abaqus automatic time stepping algorithm with CETOL = 1. × 10−5. The creep law is defined via user subroutine CREEP.