测定后张预应力摩阻损失的新方法

A New Measuring Method of Friction Losses of Prestressed Tendon in Post-tensioning

从后张预应力摩阻损失计算的基本原理出发,给出一种可有效测定摩擦系数μ、局部偏差影响系数k和锚固端摩阻损失率的新方法。该方法以实测预应力筋伸长量和千斤顶张拉力为已知条件,通过非线性方程组的数值计算求解,得到待求的参数。该方法不需要使用应力传感器,不改变预应力筋的受力状态,仅用施工现场常用量具和设备就能进行测试,测试过程简单易行,对后张预应力体系的施工与检测有重要参考价值。

This article is based on the basic principle of the calculation of friction losses of prestressed tendon in post-tensioning, and it also put forward a new method which can measure effectively coefficient of friction（g）, wobble factor （k） and the friction loss rate of anchorage zone. With the meas- ured actual elongation of prestressed tendon and the known jacking force, the method can get the unknown parameters by solving nonlinear equations. This method does not need to use stress sensor, and the test can be done with the only need of common measuring tools and equipment, and the process is simple. It has important reference value to construction and detection of post-tensioning system.