OPTIMUM SHAPE DESIGN OF SHOULDER FILLETS IN TENSION BARS AND T-HEADS

Optimum shape design of shoulder fillets in flat tension bars, round tension bars and at T-heads are considered by a mathematical programming method. The curved shape is defined by a general third degree function in the coordinates x and y which is completely determined by making use of boundary conditions and four design variables. To have a better shape control during optimization, the problem is formulated as minimization of volume with limitation on stress concentration factor. The successive optimum shapes are obtained by changing the limitation on the stress concentration factor (SCF), until minimum possible SCF limitation is reached. Design charts are presented for a few cases. It is observed that stress concentration factor can be reduced from 5 to 10% in comparison with circular fillets. © 1979.