地锚式斜拉桥收缩徐变效应测试与分析

Measurement and Analysis of Shrinkage and Creep Effect of a Ground Anchored Cable-Stayed Bridge

现行有关混凝土收缩徐变的计算公式多以试验室模型试验结果为依据确定,因此对实际结构进行长期测试以获得能够验证现行规范混凝土收缩徐变计算公式的实测数据显得尤为重要。结合湖北省郧阳汉江公路大桥,测试并分析处于自然环境中的斜拉桥在混凝土收缩徐变作用下的确切反应,在此基础上提出同时考虑混凝土温度、环境相对湿度等因素及其变化的混凝土收缩应变和徐变系数计算方法,并将之应用于实际桥梁的收缩徐变效应分析中,得出一些具有实用价值的结论。

Most of the current calculation formulas related to the concrete shrinkage and creep have been based on the laboratory model test results. It is therefore particularly important to carry out long-term field measurement for the actual structures in order to obtain the data that can verify the calculation formulas for the concrete shrinkage and creep in the current specifications. With reference to Yunyang Hanjiang River Highway Bridge in Hubei Province, the authors in this paper measure and analyze the exact response of a ground anchored cable-stayed bridge under the action of the concrete shrinkage and creep in the natural environment. On the basis of the measurement and analysis, the authors develop the method for calculating the concrete shrinkage strain and creep coefficients that take into account of both the factors and changes of concrete temperature and environment relative humidity, apply the method to the analysis of the concrete shrinkage and creep effect of the actual cable-stayed bridge and also achieve some conclusions that have practical application values.