具有初拉力的狭矩形截面(宽度与厚度之比b/h>10)张丝,其主要的计算公式有τ_(max)=hGφ/L……(1) σ_(max)=P/bh+(Eb~2/12L~2)φ~2……(2) M_x=(bh~3G/3L)φ+(b~5hE/360L~3)φ~3+(Pb~2/12L)φ……(3) (1)式中τ_(max)为自由扭转时,横截面上引起的剪应力之最大值;(2)式中σ_(max)为扭转后、横截面上引起的正应力之最大值;(3)式中第一项是由剪应力组成的扭矩;第二项是初拉力 The main formula of the narrow rectangular cross section with the initial tensile force (the ratio of width to thickness b / h> 10) is τ_max = hGφ / L σ_max = P / bh + Eb ~ 2 / 12L ~ 2 φ ~ 2 M_x = bh ~ 3G / 3L φ + b ~ 5hE / 360L ~ 3 φ ~ 3 + Pb ~ 2 / 12L φ (3) Where τ max is the maximum value of the shear stress caused by cross-section during free twisting; σ max is the maximum of normal stress caused by cross-section after torsion (3) The first term in the formula is the torque composed of shear stress; the second term is the initial tension