Abstract
The mixed mode, near-field state of stresses sourrounding a crack propagating at constant velocity is used to derive a relation between the dynamic stress-intensity factorsK I,K II, the remote stress component σ ox and the dynamic isochromatics. This relation, together with an over-deterministic least-square method, form the basis of a datareduction procedure for extracting dynamic,K I,K II and σ ox from the recorded dynamic photoelastic pattern surrounding a running crack. The overdeterministic least-square method is also used to fit static isochromatics to the numerically generated dynamic isochromatics. The resultant staticK I,K II and σ ox are compared with the corresponding dynamic values and estimats of errors involved in using static analysis to process dynamic isochromatic data are obtained. The data-reduction procedure is then used to evaluate the branching stress-intensity factor associated with crack branching and the mixed-mode stress-intensity factors associated with crack curving.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Dally, J.W., “Dynamic. Photoelastic Studies of Fracture,”Experimental Mechanics,19 (10),349–367 (Oct. 1979).
Irwin, G.R., “Discussion of the Dynamic Stress Distribution Surrounding a Running Crack—A Photoelastic Analysis,”Proc. of SESA,16 (1),93–96 (1958).
Bradley, W.B. andKobayashi, A.S., “An Investigation of a Propagating Crack by Dynamic Photoelasticity,”Experimental Mechanics,10 (3),103–113 (1970).
Bradley, W.B. andKobayashi, A.S., “Fracture Dynamics—A Photoelastic Investigation,”Eng. Fract. Mech.,3,317–332 (1971).
Kobayashi, T. and Dally, J.W., “The Relation Between Crack Velocity and Stress Intensity Factor in Birefringent Polymers,” Fast Fracture and Crack Arrest (edited by G.T. Hahn and M.F. Kanninen), ASTM STP 627, 257–273 (1977).
Kobayashi, A.S., Wade, B.G. andBradley, W.B., “Fracture Dynamics of Homalite-100,”Deformation and Fracture of High Polymers (edited by H.H. Kausch, J.A. Hassell andR.I. Jafee),Plenum Press, New York, 487–500 (1973).
Irwin, G.R., Dally, J.W., Kobayashi, T., Fourney, W.L., Etheridge, M.J. andRossmanith, H.P., “On the Determination of the »-K Relationships for Birefringent Polymers,”Experimental Mechanics,19 (4),121–128 (1979).
Rossmanith, H.P. and Irwin, G.R., “Analysis of Dynamic Isochromatic Crack-Tip Stress Patterns,” University of Maryland Report (1979).
Smith, D.G. andSmith, C.W., “Photoelastic Determination of Mixed Mode Stress Intensity Factors,”Eng. Fract. Mech.,4 (2),357–366 (1972).
Smith, C.W., Jolles, M. and Peters, W.H., “Stress Intensities for Crack Emanating from Pin-Loaded Holes,” Flaw Growth and Fracture, ASTM STP 631, 190–201 (1977).
Gdoutos, E.E. andTheocaris, P.S., “A Photoelastic Determination of Mixed-mode Stress-intensity Factors,”Experimental Mechanics,18 (3),87–96 (March 1978).
Dally, J.W. andSanford, R.J., “Classification of Stress-intensity Factors from Isochromatic-fringe Patterns,”Experimental Mechanics,18 (12),441–448 (Dec. 1978).
Sanford, R.J. andDally, J.W., “A General Method for Determining Mixed-Mode Stress Intensity Factors from Isochromatic Fringe Patterns,”Eng. Fract. Mech.,11,621–633 (1979).
Klein, G., “Spanningsfaktoren eines Risses in der Umgebung eines Kreisloches und Ihr Einfluss auf das Bruchverhalten,”Zeitschrift für Werkstofftechnik,6 (1),30–34 (1975).
Iida, S. andKobayashi, A.S., “Crack Propagation Rate in 7075-T6 Plates Under Cyclic Tensile and Transverse Shear Loading,”J. of Basic Eng., Trans. of ASME,91,Series D (4),764–769 (Dec. 1964).
Freund, L.B. andClifton, R.J., “On the Uniqueness of Plane Elasto-dynamic Solutions for Running Cracks,”J. of Elasticity,4 (4),293–299 (Dec. 1974).
Freund, L.B., “Dynamic Crack Propagation,”The Mechanics of Fracture,19,edited by F. Erdogan ASME,105–134 (1976).
Freund, L.B., “The Mechanics of Dynamic Shear Crack Propagation,”J. of Geophysical Research,84 (35),2199–2209 (1978).
Etheridge, J.M., Dally, J.W. andKobayashi, T., “A New Method of Determining the Stress Intensity Factor K from Isochromatic Fringe Loops,”Eng. Fract. Mech.,10 (1),81–93 (1978).
Kobayashi, A.S. andMall, S., “Dynamic Fracture Toughness of Homalite-100,”Experimental Mechanics,18 (1).11–18 (Jan. 1978).
Schroedl, M.A., McGowan, J.J., andSmith, C.W., “An Assessment of Factors Influencing Data Obtained by the Photoelastic Stress Freezing Technique for Stress Fields Near Crack Tips,”J. of Eng. Fract. Mech.,4,801–809 (1972).
Kobayashi, A.S., Wade, B.G., Bradley, W.B. andChiu, S.T., “Crack Branching in Homalite-100 Sheets,”Eng. Fract. Mech.,6,81–92 (1974).
Atluri, S.N., Kobayashi, A.S. andNakagaki, M., “An Assumed Displacement Hybrid Finite Element Model for Linear Fracture Mechanics,”International J. of Fract.,11,257–271 (1975).
Wade, B.G., “A Photoelastic and Numerical Study on Fracture Dynamics of Stressed Panels,” PhD thesis submitted to the University of Washington (1974).
Smith, C.W., “Stress Intensity and Flaw-shape Variations in Surface Flaws,” to be published in Experimental Mechanics.
Kalthoff, J.F., “On the Propagation Direction of Bifurcated Cracks,”Dynamic Crack Propagation (edited by G.C. Sih),Noordhoff International Leyden, 449–458 (1973).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Kobayashi, A.S., Ramulu, M. Dynamic stress-intensity factors for unsymmetric dynamic isochromatics. Experimental Mechanics 21, 41–48 (1981). https://doi.org/10.1007/BF02325929
Received:
Revised:
Issue Date:
DOI: https://doi.org/10.1007/BF02325929