基于长期温度监测的华南地区混凝土连续刚构桥梁温度变化规律研究

Research on Temperature Variations of a Concrete Continuous Rigid-Frame Bridge in South China Based on Long-Term Temperature Monitoring

以一座地处华南地区的典型混凝土连续刚构桥梁为研究对象,对其温度变化进行了长期的监测和统计分析。温度传感器是在桥梁建设施工过程中埋入混凝土内部的,能客观反映桥梁结构的温度,并在通车运营后进行了长期的监测。测量了箱梁顶板、腹板、底板等位置在太阳辐射等自然环境条件下的温度及年度内的变化规律;对箱梁腹板中间的温度监测数据进行了概率统计分析,分析表明可以用2个正态分布的线性组合描述一年时间内的温度概率密度。根据拟合结果,计算了设计基准期内结构最高季节温度,该温度值明显高于目前桥梁工程设计规范中的建议值,因此,有必要对华南地区的季节升温设计值进行更深入的研究。

A typical concrete continuous rigid-frame bridge in South China is studied and the temperature variations of the bridge are monitored in the long-term and statically analyzed. Temperature sensors are embedded in the fresh concrete of the box girder during the construction of the bridge, and data collected by those sensors can show the temperature of bridge structure objectively. Long-term monitoring is carried out during the service stage. The temperature of the roof, web and floor of box girder under natural environment such as the solar radiation are measured. And the yearly variations of the temperature are studied. The temperature data at the middle of web are statistically analyzed. The analysis showed that a linear combination of two normal distribution functions can be used to depict the probability density of the yearly temperature distribution. On the basis of fitting results, the highest season temperature in the design reference period is calculated. The calculation result is significantly higher than the recommended value in present bridge design specifications. As a. result, further study must be carried out to determine the design value of season temperature rise in South China.