Numerical contour integrations of the creep crack C∗ integral were carried out for two types of specimen. The results agree reasonably well with C∗ evaluations using limit analysis methods; path-independence of C∗ is shown. A realistic definition of the creep pseudo-stationary state is proposed and various forms of creep data input are discussed.
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References
1.
ChristianE. M.SmithD. J.WebsterG. A.EllisonE. G.‘Critical examination of parameters for predicting creep crack growth’, Advances in fracture research, ICF5, 1981, Vol. 3, p. 1295.
2.
HarperM. P.EllisonE. G.‘The use of the C parameter in predicting creep crack propagation rates’, J. Strain Analysis, 1977, 12, 167–179.
3.
EllisonE. G.HarperM. P.‘Creep behaviour of components containing cracks - a critical review’, J. Strain Analysis, 1978, 13, 35–51.
4.
NikbinK. M.SmithD. J.WebsterG. A.‘Influence of creep ductility and state of stress on creep crack growth’, ASME International Conference on Advances in Life Prediction Methods, Albany, NY, 18–20, April 1983.
5.
WuD.ChristianE. M.EllisonE. G.‘Influence of constraint on creep stress distribution in notched bars’, J. Strain Analysis, 1984, 19, in press.
6.
ChristianE. M.EllisonE. G.‘Relation between theoretical and experimental forms of theC parameter for creep cracking’, University of Bristol, Dept. of Mech. Eng. Report No. 81/10, 1981.
7.
RiceJ. R.‘A path independent integral and the approximate analysis of strain concentration by notches and cracks’, J. Appl. Mech., Trans. ASME, 1968, 35, 379–386.
8.
LandesJ. D.BegleyJ. A.‘A fracture mechanics approach to creep crack growth’, Mechanics of crack growth, 1976, ASTM STP 590, pp. 128–148.
9.
GoldmanN. L.HutchinsonJ. W.‘Fully plastic crack problems: The center-cracked strip under plane strain’, Int. J. Solids Structures, 1975, 11, 575–591.
10.
PennyR. K.MarriottD. L.Design for creep, 1971 (McGraw-Hill, London) pp. 104–110.
11.
ChristianE. M.EllisonE. G.‘Approximate methods for numerical creep analysis using a two-bar structure’, University of Bristol, Dept. of Mech. Eng. Report No. 81/13, 1981.
12.
RiedelH.‘A contribution to the theory of fracture mechanics under creep conditions’, International Conference on Engineering Aspects of Creep, Vol. 1, 1980 (IMechE, London) pp. 215–218.
13.
NikbinK. M.WebsterG. A.TurnerC. E.‘Relevance of non-linear fracture mechanics to creep cracking’, Cracks and Fracture, 1976, ASTM STP 601, pp. 47–62.
14.
HaighJ. R.RichardsC. E.‘Yield point loads and compliance functions of fracture mechanics specimens’, CEGB Report RD/L/M461, June 1974.
15.
PatersonA. J. F.Creep and fatigue interaction in a low alloy steel, PhD thesis, University of Bristol, 1973.
16.
EllisonE. G.PatersonA. J. F.‘Creep fatigue interactions in a 1 Cr Mo V steel’, Proc. Instn mech. Engrs, 1976, 190, 319–330.
17.
EllisonE. G.HarperM. P.‘The influence of constraint on creep fracture’, University of Bristol, Dept. of Mech. Eng. Report No. 79/5, July 1979.
18.
ChristianE. M.EllisonE. G.‘A mesh verification exercise using the BERSAFE system’, University of Bristol, Dept. of Mech. Eng., Report No. 82/5, 1982.
19.
OwenD. R. J.NayakG. C.KfouriA. P.GriffithsJ. R.‘Stresses in a partly yielded notched bar’, Int. J. Numer. Methods Engng., 1973, 6, 63–73.
20.
HellenT. K.‘Numerical methods in fracture mechanics’, Developments in fracture mechanics - I, 1979 (Applied Science Publishers, London), ch. 5.
21.
HayhurstD. R.HendersonJ. Y.‘Creep stress redistribution in notched bars’, Int. J. Mech. Sci., 1977, 19, 133–146.
22.
HultJ.‘On the stationarity of stress and strain distribution in creep’, inSecond order effects in elasticity, plasticity, and fluid dynamics, (IUJAM Symposium, Haifa) pp. 352–361.
23.
AinsworthR. A.‘Some observations on creep crack growth’, CEGB Report RD/B/N4868, July 1980.
24.
EhlersR.RiedelH.‘A finite element analysis of creep deformation in a specimen containing a macroscopic crack’, Advances in fracture research, 1981, ICF5, Vol. 2, pp. 691–704.
25.
KumarV.GermanM. D.ShihG. F.‘Estimation technique for the prediction of elastic-plastic fracture of structural components of nuclear systems’, GEC, Schenectady, NY, Report No. SRD-80–094.
26.
EllisonE. G.MusiccoG. G.‘Notch rupture and crack growth behaviour under creep conditions’, Adv. Seminar on Fracture Mechanics, ASFM 3, Ispra, Italy, Oct. 1981.
