[提要]  通过对72根冷拔螺旋肋钢筋拔出试验的研究，分析了冷拔螺旋肋钢筋的粘结锚固特点和各主要因素对平均粘结强度的影响，回归了平均粘结强度的计算公式，推导了在拉拔状态下临界锚固长度的计算公式，并给出了在各种情况下的临界锚固长度值。
[关键词]  冷拔螺旋肋钢筋  粘结锚固

Based on the results of pull-out test of 72 cold-draw spiral bars, the bond and anchor property between the bar and concrete and the factor such as the tensile strength of concrete, the thickness of relative protective layer and the relative anchoring length that influence the average bond strength are discussed in detail. The formulas to calculate the average bond strength and the minlmum anchoring length and the value of minimum anchoring length are given.
Keywords:  cold-draw spira! bar; bond; anchor; property