预应力混凝土连续梁桥管道摩阻实验

Experiment on prestress tube frictional resistance of prestressed concrete continuous girder bridge

针对预应力摩阻损失设计参数的规范值一般小于实测值的情况,基于预应力管道摩阻实验原理和实验方法,对某连续梁桥进行纵向预应力管道摩阻测试,并采用最小二乘法对现场测试数据进行分析处理。结果表明,摩阻参数k的设计值与规范值相同,实验值偏大;μ的设计值偏小,需在计算模型中修正。实测预应力筋伸长量与设计理论值的误差小于6%,符合规范要求,验证了实验方法的可行性。该研究可为梁桥施工监控中的应力分析和线形控制提供可靠的对比依据。

Aimed at addressing the code value of the prestressed friction loss design parameter lower than the measured value,this paper describes the test of the longitudinal prestressed tube＇s friction coefficient of a continuous girder bridge,based on the principles of prestressed tube friction testing and test method,and the analysis of the field test data by using least-squares method.The results indicate that,the same design value of k as the code value results in a little larger measured value,and a lower design value of μ,both of which should be corrected in the calculation model.The error between the measured value and the code value of prestressed reinforcement＇s elongation was lower than 6%,as required by the code,which proves the feasibility of the test method.This research provides a reliable calculation parameters for the stress analysis and linear control during construction monitoring.