Hey everybody, Anyone knows the reason why we use radius for solid section ? Solid section seems like a bullet. I accually prefer to do without radius, if any good reason does not exist.
The fillet curvature is there to reduce stress concentrations. However the reason you do not use a simple specimen with the same diameter throughout is because you want failure to occur at the reduced section (preferably in the middle) and not at the ends of specimens located in the grips.
the design or geometry of reduced section (curve/radius) is to lessen or reduce the amount of stress concentration during testing. the higher the stress concentrations are, the lower is the measured strength.