摘要
为掌握电缆发热对钢箱梁温度分布的影响规律,准确预测内敷电缆钢箱梁全寿命周期内的夏季极端温度值,以舟岱大桥为例,采用计算流体动力学模拟方法构建了含电缆的钢箱梁全尺寸热场数学模型,模型综合考虑了外界环境温度、风速和太阳辐射的共同影响,分析了夏季极端气候条件下电缆发热对钢箱梁内部温度场的影响规律。结果表明:钢箱梁横截面的温度模拟结果与嘉绍大桥现场实测数据趋势一致,表明CFD模型具有较高的可信度和准确性;钢箱梁腔体温度主要受外部气象条件的影响,而电缆发热对钢箱梁腔体温度的影响有限,相较于无电缆工况,内敷额定载流量1 540 A的双回路电缆使得钢箱梁内环境温升小于3℃;基于近60年舟山定海气象站的长序列气象资料,模拟获取历年夏季钢箱梁内部平均温度极值,并利用皮尔逊Ⅲ分布回归得到50年一遇和百年一遇的钢箱梁夏季内部平均温度极值分别为56.3℃和57.2℃,而钢箱梁内部平均温度达到60℃的重现期为1 129年,在钢箱梁的正常服役年限内很难出现。研究成果可为类似工程确定电缆载流量、保证电缆运行热安全提供基础数据,为主管和决策部门进行分析、评价提供技术支撑。
To master the influence rule of cable heating on the temperature distribution of steel box girder, and accurately predict the summer extreme temperature in the whole life cycle of the steel box girder with internal cable, taking the Zhoudai Bridge for example, a full-scale thermal field mathematical model of steel box girder with cable is established by computational fluid dynamics(CFD) simulation. The model comprehensively considers the combined influence of external ambient temperature, wind speed and solar radiation. The influence rule of cable heating on the internal temperature field of steel box girder under extreme weather condition in summer is analyzed. The result shows that(1) The temperature simulation result of the steel box girder’s cross-section is consistent with the measured data of the Jiashao Bridge, indicating that the CFD model has high reliability and accuracy.(2) The temperature of the steel box girder is mainly affected by external meteorological condition, while the influence of cable heating is limited. Compared with the condition without cable, the internal double circuit cable with a rated ampacity of 1 540 A makes the temperature rise of the steel box girder less than 3 ℃.(3) Based on a long sequence of meteorological data from Zhoushan Dinghai weather station in recent 60 years, the maximum average temperature in steel box girders in summer over the years are obtained through simulation. The extreme average temperatures of steel box girder in summer with reappearance periods of 50 years and 100 years are 56.3 ℃ and 57.2 ℃ respectively by using the Pearson III distribution regression, while the reappearance period of the average temperature inside the steel box girder reaching 60 ℃ is 1 129 years, which hardly happens during its normal service life. The research result can provide basic data for similar projects to determine the ampacity of the cables and ensure thermal safety of cable operation, and provide technical support for the analysis and evaluation of supervisors and
作者
侯云鸽
章李刚
陈小峰
吴珂
HOU Yun-ge;ZHANG Li-gang;CHEN Xiao-feng;WU Ke(Key Laboratory of Offshore Geotechnics and Material of Zhejiang Province,Zhejiang University,Hangzhou Zhejiang 310058,China;Center for Balance Architecture,Zhejiang University,Hangzhou Zhejiang 310007,China;Engineering Research Center of Oceanic Sensing Technology and Equipment of MOE,Zhejiang Lniversity,Zhoushan Zhejiang 316021,China;Zhejiang Huayun Electric Power Engineering Design&Consulting Co.,Ltd.,Hangzhou Zhejiang 310014,China)
出处
《公路交通科技》
CAS
CSCD
北大核心
2022年第3期85-90,共6页
Journal of Highway and Transportation Research and Development
基金
浙江省自然科学基金项目(LY19E080028)
宁波市交通运输科技计划项目(202113)。
关键词
桥梁工程
极端温度
数值模拟
跨海大桥
钢箱梁
内敷电缆
重现期
bridge engineering
extreme temperature
numerical simulation
crossing-sea bridge
steel box girder
internal cable
reappearance period
