4.8.27 Test 12C: 2-D plane stress – stepped load, primary-secondary creep

Product: ABAQUS/Standard  

Element tested

CPS8R   

Problem description

Material:

Young's modulus = 200 × 103 N/mm2, Poisson's ratio = 0.3, Creep law: = A A, A = 10–16, A = 10–14, = 5.0, and m = 0.5.

Boundary conditions:

on line AD and at mid-point of line AD.

Loading:

= 100 N/mm2 for 10000 hours and = 110 N/mm2 for 10000 hours.

Reference solution

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

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
t
0.000.0000 (0.00%)
147.210.0013 (–5.29%)
1580.800.0055 (–1.62%)
8800.000.0181 (–0.54%)
15028.000.0316 (–0.32%)
18438.000.0393 (–0.26%)
20000.000.0427 (–0.23%)

Remarks

The total creep time for this test is 20000 hours. The times listed in the above table are the times calculated by the ABAQUS automatic time stepping algorithm with CETOL = 0.1. The creep law is defined via user subroutine CREEP.

Input files

ncrccr8x.inp

CPS8R elements.

ncrccr8x.f

User subroutine CREEP used in ncrccr8x.inp.