摘要
无铺装钢箱梁是一种应用于高速轨道交通中的新结构。不均匀的日照温度场会使其产生较为复杂的应力和变形,从而影响结构的安全性和行车的舒适性,故对日照温度场影响因素的研究是必要的。通过对无铺装轨道钢箱梁足尺试验模型长达3个月的温度监测,发现在温度梯度规律较显著的4 d中,最大温度梯度总是出现在3#腹板上,出现的时间段为12:00~16:00。根据热力学和有限元理论,采用ANSYS软件建立二维有限元模型得到各时刻各腹板的计算温度梯度曲线。将计算温度梯度曲线与实测温度梯度曲线对比分析,发现两者吻合良好。对两大类参数开展了敏感性分析,发现对最大温度梯度影响最显著的参数为太阳辐射吸收率,其次为翼缘板长度及日平均风速。通过减少顶板上表面的对风起阻挡作用的障碍物、减小翼缘板长度及采用白色或浅色涂装能够有效地减小无铺装轨道钢箱梁的最大温度梯度。
Steel box girder without pavement is a new type of structure used in high-speed rail transportation.Nonuniform sunlight temperature can cause complicate stress and deformation in this kind of structure,affecting structure safety and driving comfortability.It is necessary to study the influencing factors of the nonuniform sunlight temperature field.Through three-month temperature monitoring on full-scale test model,it was found that the maximum temperature gradient always appeared on the No.3 web during 12:00~16:00 in the four days with most remarkable temperature gradient.By adopting thermodynamics and finite element method,a planar finite element model was developed in ANSYS to get calculated temperature gradient curves of each web.By comparing the calculated temperature curves with that measured,good matching was found.Sensitivity analysis was carried out for two types of parameters.It was found that the solar radiation absorption rate is the most sensitive parameter followed by the length of the flange slab and the daily average wind speed.Lessening wind obstacle on the top of the girder,reducing the length of the flange slab and using white or light coating can efficiently reduce the maximum temperature gradient of the girder without pavement.
作者
黎泰良
LI Tai-liang(China Railway Siyuan Group Southwest Survey and Design Co.Ltd.,Kunming 650206,China)
出处
《工程建设与设计》
2022年第1期56-60,共5页
Construction & Design for Engineering
关键词
桥梁工程
温度场
无铺装钢箱梁
有限元法
敏感性分析
bridge engineering
temperature field
steel box girder without pavement
finite element method
sensitivity analysis
