caa a22 4500 465741878 CHVBK 20180323111810.0 cr unu---uuuuu 170327e19901101xx s 000 0 eng 10.1007/BF00041997 doi (NATIONALLICENCE)springer-10.1007/BF00041997 Inclusion of primary creep in the estimation of the C t parameter [Elektronische Daten] [Chun-Pok Leung, David McDowell] The problem of time-dependent fracture under transient creep conditions is investigated via finite element analyses of fracture specimens with stationary cracks. The constitutive models consist of linear elasticity with combinations of power-law secondary creep and two primary creep laws. Two proposed parameters are studied. One is a contour integral, C(t), which characterizes the crack tip singularity strength. The other one, C t, is evaluated based on the load line deflection rate and has been used successfully in correlating experimental creep crack growth data. It is evident that accurate constitutive modeling is essential to good agreement with experimental data. The inclusion of primary creep resolves earlier discrepancies between the experimental and analytical load line deflection rates which are used to calculate the respective values of C t. The loading boundary condition is also an important factor that has been addressed. A more general formulation of C twhich includes primary creep is presented. In small scale and transition creep, the C tparameter does not characterize the crack tip stress singularity but rather is related to the crack tip creep zone growth rate. At times past transition time, C tand C(t) both approach a path-independent integral, C *(t), which characterizes the stationary crack tip stress field. The relationship between C tand C(t) is discussed. The interpretation and estimation of the C tparameter are given based on the numerical results and analytical manipulations. Kluwer Academic Publishers, 1990 Leung Chun-Pok School of Mechanical Engineering, Georgia Institute of Technology, 30332, Atlanta, Georgia, USA aut McDowell David School of Mechanical Engineering, Georgia Institute of Technology, 30332, Atlanta, Georgia, USA aut International Journal of Fracture Kluwer Academic Publishers 46/2(1990-11-01), 81-104 0376-9429 46:2<81 1990 46 10704 https://doi.org/10.1007/BF00041997 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00041997 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Leung Chun-Pok School of Mechanical Engineering, Georgia Institute of Technology, 30332, Atlanta, Georgia, USA aut NATIONALLICENCE 700 1- McDowell David School of Mechanical Engineering, Georgia Institute of Technology, 30332, Atlanta, Georgia, USA aut NATIONALLICENCE 773 0- International Journal of Fracture Kluwer Academic Publishers 46/2(1990-11-01), 81-104 0376-9429 46:2<81 1990 46 10704 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer