Previously, in "assumed calculation" of extrusion stress of round-head rivet and round hole, it was considered that maximum non-uniform extrusion stress equals approximately to the value obtained from dividing extrusion force by area of diametral plane of round-head rivet or round hole. 在圆钉与圆孔的挤压应力假定计算中,曾认为:以挤压力除以圆孔或圆钉的直径平面的面积所得的挤压应力与理论分析的最大应力大致相等。