为使偏轴应变法能准确测试钢绞线所受拉力的大小,通过考虑钢绞线形状、泊松比效应等对偏轴应变与轴向应变的关系进行理论推导,并对4根7.5m长、20根0.8m长钢绞线进行张拉试验,采集了952个有效数据,基于理论推导及试验数据对钢绞线偏轴应变与轴心应变之间的关系进行了研究。结果表明:经理论推导由偏轴应变法得到的1×7Φ15.2钢绞线内力比其实际内力偏小5.73%;对于长、短钢绞线由偏轴应变法得到的拉力修正系数较为一致,通过Lorentz及Gauss函数拟合得出利用偏轴应变乘以名义弹性模量得到的计算应力比实测应力偏小约6.5%;综合理论推导及试验结果建议采用偏轴应变法测试钢绞线拉力时应乘以修正系数1.06。 In order to enable the off-axis strain method to accurately test the tensile force of the strand, the theoretical derivation of the relationship between the off-axis strain and the axial strain is made by considering the strand shape and Poisson’s ratio effect. Length, 20 0.8m long strands for tension test, collected 952 valid data, based on theoretical deduction and experimental data on the strand between the off-axis strain and axial strain was studied. The results show that the theoretic deduction derived by the off-axis strain method of 1 × 7Φ15.2 steel wire internal force is smaller than its actual internal force 5.73%; for long and short steel strands obtained by the off-axis strain correction coefficient is consistent , And the calculated stress obtained by multiplying the off-axis strain by the nominal elastic modulus by Lorentz and Gauss function fitting is smaller than the measured stress by about 6.5%. Based on the comprehensive theory deduction and the test results, it is suggested that the off-axis strain method is used to test the strand tension Should be multiplied by a correction factor of 1.06.