钢筋试样抗拉强度为: P62.0×103 548N/mm2 b 丌×6 P63.4×10 b 2 =561N/mm 丌×6 ab=(548+561)÷2=555N/mm2 钢筋试样伸长率为: 0 70.6-60 17.7 60 l1-l071.4-60 =19.0% 60 5=(17.7+190)÷2=18.4%钢筋试样抗拉强度为： 2 2 3 1 548 / 6 6 2.0 1 0 N mm A P b =   = =   2 2 3 2 561 / 6 63 .4 10 N mm A P b =   = =   σb =(548+561)÷2 = 555 N/mm2 钢筋试样伸长率为： 1 7 .7% 6 0 7 0 .6 6 0 0 1 0 5 = − = − =  l l l  19 .0% 60 71 .4 60 0 1 0 5 = − = − =  l l l  δ=(17.7+19.0)÷2 =18.4%