EFFECT OF FIBER GEOMETRY ON STRESS IN FIBERREINFORCED COMPOSITE MATERIALS. PHASE 2.

Six additional two-dimensional photoelastic models of fiber-reinforced composite material configurations were constructed and tested to study the effects on the shear stress distribution in an elastic matrix of 1 a gradually tapered fiber, 2 a fiber whose end was unbonded from the matrix, and 3 aligned fibers having various gap lengths between fiber ends. The tapered and unbonded fiber ends were found to produce somewhat higher peak stresses in the matrix than fiber end shape models tested in the phase 1 investigation. It made little difference whether the gap between aligned fiber ends was open, simulating a void resulting from a broken fiber, or filled with matrix material. Author