4.8.23 Test 10C: 2D plane stress – biaxial (negative) stepped load, primary 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 = 3.125 × 10^–14 per hour ( in N/mm²), n = 5, m = 0.5.

Boundary conditions:

on line AD and on line AB.

Loading:

= 200 N/mm² for 100 hours and = 250 N/mm² for 100 hours;

= –200 N/mm² for 100 hours and = –250 N/mm² for 100 hours.

Reference solution

This is a test recommended by the National Agency for Finite Element Methods and Standards (U.K.): Test 10(c) from NAFEMS Publication Ref: R0027, “NAFEMS Fundamental Tests of Creep Behaviour,” June 1993.

		for 100 hours
Time hardening:		for hours
Strain hardening:		for hours

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
Time Hardening		Strain Hardening
t		t
0.00	0.0000 (0.00%)	0.00	0.0000 (0.00%)
0.52	0.0976 (–0.19%)	0.52	0.0978 (–0.05%)
8.39	0.3909 (–0.03%)	8.39	0.3910 (0.00%)
76.78	1.1828 (–0.01%)	76.78	1.1829 (0.00%)
136.78	2.0483 (–0.01%)	136.78	2.8399 (–0.22%)
176.78	2.7077 (–0.01%)	176.78	3.8541 (–0.01%)
200.00	3.0564 (0.00%)	200.00	4.3354 (0.00%)

Remarks

The total creep time for this test is 200 hours. The times listed in the above table are the times calculated by the Abaqus automatic time stepping algorithm with CETOL = 5. × 10^–3.

Input files

ncracr8t.inp

Time hardening.

ncracr8s.inp

Strain hardening.