Photoelastic Study of Rectangular Plates under Bending

Abstract

A systematic analysis by the method of laminated plate photoelasticity was conducted to determine the distribution of bending moment in rectangular plates fixed along one side and subjected to a concentrated load. About 140 cases were treated by successively varying the shape factor of the plate B/l and location of the loading point X_p/l, Y_p/l. After the distribution of the differences of principal moments M₁-M₂ was obtained, the distribution of the sums of principal moments M₁+M₂ was evaluated on a computer conforming to the solution of Poisson's equation, using the boundary condition obtained photoelastically. As the effects of finite thickness of the model plate and membrane forces due to finite deflection were corrected satisfactorily, the results obtained were related to ideally thin plates under negligibly small deflection. The relations between the maximum bending moment and B/l and X_p/l, Y_p/l were given in detail. Comparison of the experimental results with available theoretical values for a special case where B/l→∞ indicated an excellent agreement.