The SCF at the bottom of U-shaped notch of three-point bending beam is smaller than that of the counterpart pure bending beam, and the largest relative difference is -7.3%.

• 将U形切槽梁三点弯曲的应力集中系数与对应的U形切槽梁纯弯曲的应力集中系数作比较，发现前者比后者小，最大相对偏差达到-7.；3%25。