钢箱混凝土组合拱桥施工过程中温度效应分析

Temperature Effect Analysis of Steel-Box Concrete Composite Arched Bridge in Construction Process

钢箱-混凝土组合拱桥施工过程中在整体温度变化和日照温度变化作用下的应力及变形影响不可忽略。以重庆江津笋溪河大桥为例,对施工过程中整体温度变化和日照温度变化作用下的主拱应力、结构变形及温度场分布进行研究。结果表明:整体温变作用下应力和变形随温度增加而增加,空钢箱阶段最不利位置位于拱脚处,最大应力增量达40 MPa,主拱成型阶段最不利位置位于主拱3/8 L处,最大应力增量达25 MPa;日照作用下,成拱后钢箱-混凝土组合结构拱桥由于内部混凝土的热传导作用,钢箱与混凝土的温度及应力相对均匀,钢箱两侧温度基本相等,钢箱上下缘有一定的温度差。

In the construction process,the stress and deformation effects of steel-box concrete composite arched bridge under the overall temperature change and sunlight temperature change cannot be neglected. Taken the Sunxi River bridge in Jiangjin as a study object,construction steel box stress,structural deformation and temperature distribution under the overall temperature change and sunlight temperature change were in-depth studied. The results show that the overall effect of temperature change under stress and deformation increases with temperature. At the empty steel box stage the most unfavorable position locates at the foot arch,and the maximum stress increments up to 40 MPa. At the main arch forming stage the most unfavorable position is at the main arch 3 /8L,and the maximum stress increments up to 25 MPa. Under the influence of sunshine,due to internal heat conduction concrete,the temperature and stress of steel-box and concrete relatively uniform; the steel tank temperature substantially equals on both sides; the top and bottom edge of the steel box have a certain temperature difference.