【摘要】 基于1年多的实测温度和气象数据,使用统计学和极值分析等理论,对长江下游某大跨斜拉桥倒Y形混凝土桥塔有效温度变化规律、预测方法以及极值进行了分析研究.结果表明:桥塔有效温度近似以年为周期呈正弦式变化,并在2.0～31.3℃之间波动;桥塔日最高和最低有效温度分别主要发生于22∶00—00∶00和10∶00—12∶00之间,桥塔日最高有效温度的发生时间与日最高气温相比滞后6.5 h左右,桥塔日最高有效温度的发生时间与日最低气温相比滞后4.5 h左右;桥塔的日最高和最低有效温度均与连续6 d平均日最低气温的相关性最大,相关系数分别可达0.982和0.981,故使用连续6 d平均日最低气温能对桥塔日最高和最低有效温度进行较为准确的预测;桥塔最高和最低有效温度的50年一遇标准值分别为38.65和-1.84℃,100年一遇标准值分别为39.61和-2.69℃.更多还原

【Abstract】 Based on more than one-year measured temperature and meteorological data, the variation rule, the prediction method and the extreme values of an inverted Y-shaped concrete pylon in the lower area of the Yangtze River were studied by statistical theory and extreme value analysis. The results show that the effective temperature of the pylon changes between 2.0 to 31.3 ℃ as sine functions with a periods of one year. The daily maximum and the minimum effective temperatures of the pylon mainly appear 22∶00 to 00∶00 and 10∶00 to 12∶00, respectively. The occurrence time of the daily maximum effective temperature is about 6.5 h later than that of the daily maximum air temperature, while the occurrence time of the daily minimum effective temperature is about 4.5 h later than that of the daily minimum air temperature. The daily maximum and the daily minimum effective temperatures of the pylon have maximal relationship with the average daily minimum air temperature for 6 consecutive days, and the correlation coefficients can reach 0.982 and 0.981, respectively. Therefore, the daily maximum and minimum effective temperatures of the pylon can be predicted accurately by using the average daily minimum air temperature for 6 consecutive days. The maximum and the minimum effective temperatures of the pylon are 38.65 and-1.84 ℃ respectively within the 50-year return period, and were 39.61 and-2.69 ℃ respectively within the 100-year return period.更多还原