New Shear Strength Test for Solid Wood


  • J. Y. Liu


Shear strength, shear test, wood, wood grain


A new method for testing material properties has been applied to determine the shear strengths of specimens of Sitka spruce and Douglas-fir. The method permits the realization of pure shear in the critical section of the specimen. Pure shear is not achieved in the current American Society for Testing and Materials (ASTM) shear test. The large strength ranges of wood fibers and the vast differences in strength between earlywood and latewood fibers can still cause significant scatter in the test data, but the effect of combined stresses can be effectively controlled. Because of the special properties of wood, failure always follows the slope of the grain. The new method can only yield shear strength parallel to grain, which is required for engineering design purposes.


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