Strength of Wood Beams with Filleted Interior Notches: A New Model
Keywords:
Beam, fillet, finite element modeling, notch, strength measurement, strength predictionAbstract
A critical fillet hoop stress (CFHS) model has been used to develop an expression for predicting the failure loads of beams with notches on the tension side between the supports. The effects of notch location and loading condition are described well by a single parameter, V/M, the ratio of resultant shear to resultant moment at the section containing the critical notch fillet. Effects of notch depth, fillet radius, and beam depth are treated explicitly in the model. Computer modeling and mechanical testing showed negligible effects of notch length and beam span. The model has been verified with notched beam tests of eight wood materials, three notch locations, and twenty-one filleted notch geometries. The closed-form strength equation, with a single material parameter (k), accurately described the observed trends in experimental notched beam critical loads with respect to notch and beam geometry, notch location, and loading geometry.References
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