An Investigation of the Fracture of Butt Joints in Parallel-Laminated Veneer

Authors

  • Joseph Jung
  • Joseph F. Murphy

Keywords:

Parallel-laminated veneer, butt joints, fracture mechanics, joint spacing

Abstract

A finite-element analysis and experimental testing program was conducted to investigate the fracture mechanics aspects of butt joints in parallel-laminated veneer (PLV). The effects of the number of plies, ply thickness, and joint spacing were investigated. It was found that the isotropic and orthotropic solutions for edge-cracked specimens were very close. Also, the increase in the stress-intensity factor for the exterior butt joint was of the order of only 4% for a joint separation spacing of four ply-thicknesses. In general, it was found that Mode I fracture toughness increased with decreasing veneer thickness and that the fracture toughness of exterior butt-jointed specimens varied with veneer thickness and number of plies. Results of the butt-joint interaction tests indicate a much higher degree of joint interaction than predicted by the finite-element analysis.

References

Atluri, Satya N., Albert S. Kobayashi, and Michihiko Nakagaki. 1975a. An assumed displacement hybrid finite-element model for linear fracture mechanics. Int. J. Fract. Mech.11(2):257-271.nAtluri, Satya N., Albert S. Kobayashi, and Michihiko Nakagaki. 1975b. A finite-element program for fracture mechanics analysis of composite material. ASTM STP 593, pp. 86-98.nBarrett, J. D. Shear fracture of wood. 1976. Int. Union of For. Res. Organ. Congr., Oslo, Norway.nBarrett, J. D., and R. O. Foschi. 1971. Mode II stress-intensity factors for cracked wood beams. Eng. Fract. Mech.9(2):371-378.nBroek, David. 1974. Elementary engineering fracture mechanics. Noordhoff Int. Publ., Leyden, The Netherlands.nForest Products Laboratory Press-Lam Team. 1976. Press-Lam: Progress in technical development of laminated veneer structural products. USDA For. Serv. Res. Pap. FPL 279. For. Prod. Lab., Madison, WI.nKendall, Maurice G., and Alan Stuart. 1961. The advanced theory of statistics.2(3):130-132. Hafner Publ. Co., New York, NY.nLei, Young-Kong, and James B. Wilson. 1979. Fracture toughness of parallel-laminated veneer. For. Prod. J.29(8):28-32.nLeicester, R. H., and P. C. Bunker. 1969. Fracture at butt joints in laminated pine. For. Prod. J.19(2):59-60.nMindess, S., J. S. Nadeau, and J. D. Barrett. 1975. Slow crack growth in Douglas-fir. Wood Sci.8(1):389-396.nMoody, R. C., and C. C. Peters. 1972. Feasibility of producing a high-yield laminated structural product: Strength properties of rotary knife-cut laminated southern pine. USDA For. Serv. Res. Pap. FPL 178. For. Prod. Lab., Madison, WI.nMurphy, J. F. 1979. Using fracture mechanics to predict failure of notched wood beams. Proc. First Int. Conf. on Wood Fracture 1978, Banff, Alberta.nPenny, Dwight T. 1977. Fracture mechanics analysis of butt joint in laminated wood beams. M.S. thesis. Dep. of Mech. Eng., Colo. State Univ., Fort Collins, CO.nSchaffer, E. L., R. W. Jokerst, R. C. Moody, C. C. Peters, J. L. Tschernitz, and J. J. Zahn. 1972. Feasibility of producing a high-yield laminated structural product: General summary. USDA For. Serv. Res. Pap. FPL 175. For. Prod. Lab., Madison, WI.nSchniewind, A. P., and J. C. Centeno. 1973. Fracture toughness and duration of load factor I. Six principal systems of crack propagation and the duration factor for crack propagating parallel to grain. Wood Fiber5(2):152-159.nSchniewind, A. P., and D. E. Lyon. 1973. A fracture mechanics approach to the tensile strength perpendicular to grain of dimension lumber. Wood Sci. Technol.7:45-59.nSchniewind, A. P., and R. A. Pozniak. 1971. On the fracture toughness of Douglas-fir wood. Eng. Fract. Mech.2:223-233.nSih, G. C., P. C. Paris, and G. R. Irwin. 1965. On cracks in rectilinearly anisotropic bodies Int. J. Fract. Mech.1:189-203.nSmith, F. W., and D. T. Penny. 1980. Fracture mechanics analysis of butt joints in laminated wood beams. Wood Sci.12(4):227-235.nTada, Hiroshi, Paul C. Paris, and George R. Irwin. 1973. The stress analysis of cracks handbook Del. Res. Corp.nUeng, C. E. S., J. A. Aberson, and B. A. Lafitte. 1977. Tensile analysis of an edge notch in a unidirectional composite. J. Composite Mater.11:222-235.nUnited States Department of Agriculture, Forest Service, Forest Products Laboratory. 1974. Wood handbook: Wood as an engineering material. U.S. Dep. of Agric. Handb. No. 72 (rev.). Washington, DC.nWalsh, P. F. 1973. The interaction of butt joints. J. Int. Wood Sci.6(2):22-27.nWalsh, P. F., R. H. Leicester, and A. Ryan. 1973. The strength of glued lap joints in timber. For. Prod. J.23(5):30-33.nWu, E. M. 1967. Application of fracture mechanics to anisotropic plates. J. Appl. Mech.34:967-974.n

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Published

2007-06-27

Issue

Number 2 / April 1983

Section

Research Contributions

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