Outer Fiber Strain Factor

For rectangular specimens in a 4-point bend test: Outer fiber strain factor = (support span2 * (3 - (1 - load span/support span)2))/(thickness * 12) For rectangular specimens in a 3-point bend test: Outer fiber strain factor = support span2/(thickness * 6) For cylindrical specimens in a 4-point bend test: Outer fiber strain factor = (support span2 * (3 - (1 - load span/support span)2))/(diameter * 12) For cylindrical specimens in a 3-point bend test: Outer fiber strain factor = support span2/(diameter * 6)