施工阶段钢绞线摩阻损失变化规律探索

Probe into Change Rules of Friction Loss of Steel Stranded Wires during Construction

对钢绞线张拉理论精确伸长量和预应力损失之间的关系进行初步分析。在几个施工现场进行钢绞线逐级张拉试验,得出在较高锚下应力度下,实际摩阻损失与锚下应力大致呈线性规律变化。通过设置线性起始点偏差的阀值,来分析不同长度钢绞线的合理初应力起算点。通过分析伸长量偏差与预应力损失偏差的比值,初步得出伸预率比与钢绞线长之间的线性变化规律。

This paper conducts preliminary analysis for the correlation between the accurate elongation and loss of prestress of steel stranded wires in tension theory. By performing tension tests step by step on several construction sites, the paper obtains that the actual loss of friction loss and stress under anchor approximately exhibit regular linear changes at high stress under anchor. By setting the threshold value of linear initial deviation, the paper analyzes the starting point of reasonable initial stress of steel stranded wires at different lengths. The paper preliminarily obtains the linear change rule between the ratio of elongation to prestress and the length of steel stranded wires through analysis for the ration of elongation deviation to the deviation of prestress loss.