双箱单室钢箱梁摊铺沥青混凝土时的温度荷载模式

城市中小跨径钢桥逐渐采用沥青混凝土摊铺,沥青混凝土高温摊铺会对桥梁结构产生影响,需建立沥青混凝土高温摊铺时的温度荷载计算公式对不同类型桥梁进行分析。采用ANSYS建立钢箱梁节段瞬态热传导模型,分析浇筑式沥青混凝土摊铺过程中双箱单室钢箱梁温度场的分布特征。根据仿真结果建立了温度荷载计算公式,并利用热-结构耦合分析模型与梁单元模型讨论温度荷载公式在梁单元模型中的适用性。研究结果表明:采用温度荷载计算公式计算支座纵向位移时误差较小,计算支座竖弯转角时误差较大,计算支座竖向反力及梁体竖向位移时误差在10%以内。

Study on Temperature Load Pattern in Double-Box Single-Cell Steel Box Girder During Asphalt Concrete Paving at High Temperature

Asphalt concrete paving is gradually used for medium and small span steel municipal bridges.Asphalt concrete paving at high temperature will affect bridge structure.It is necessary to establish a formula for calculating temperature load of asphalt concrete paving at high temperature to analyze different types of bridges.A transient heat conduction model of steel box girder segment was established by ANSYS,and the distribution characteristics of the temperature f ield of double-box single-cell steel box girder in the process of paving with cast-in-place asphalt concrete were analyzed.According to the simulation results,a formula for calculating temperature load was established,and the applicability of the temperature load formula in the beam element model was discussed by using the thermal-stress coupling analysis model and the beam element model.The analysis results show that the error of calculating the vertical displacement of the bearing by using the formula of temperature load is smaller,and the error of calculating the vertical bending angle of the bearing is larger.The error of calculating the vertical reaction force of the bearing and the vertical displacement of the beam is less than 10 %.