柱板式空心墩温度效应分析研究

摘要

To examine the distribution condition of temperature field and temperature effect on the high-rise column-plate hollow piers under the action of sunshine and cold wave ,the high-rise column-plate hollow piers of a railway prestressed concrete continuous rigid-frame bridge was taken as the study background .The temperature distribution of each cross section of the pier along the wall thickness under the action of sunshine and cold wave were measured .The temperature effect of the pier of such type under the action of sunshine and cold wave was gained through finite element analysis .The numerical regression analysis method was used to gain the fitting function of the temperature difference gradient of the walls of the column-plate hollow piers and the simplified model of the temperature load application calculation .The results of the study indicated that the influential depth of the ambient temperature variation on the walls of the column-plate hollow piers was only about 60 cm ,and the temperature showed the trait of non-linear variation along the depth of the concrete plate .Under the action of the sunshine ,greater tensile stress and compressive stress occurred at the turn-down corners of the column-plate transitional section .While under the action of cold wave ,greater tensile stress was found in the turn-down corners in the column-plate transitional section .The temperature gradient along the plate thickness of the column-plate hollow piers showed the way of exponential function distribution ,after simplified ,the temperature gradi-ent can adopt the kinked-line temperature load model .%为了解柱板式空心高墩在日照升温和寒潮降温作用下温度场及温度效应的分布情况，以某铁路预应力混凝土连续刚构桥的柱板式空心高墩为背景，实测柱板式高墩各测试截面在日照升温和寒潮降温作用下沿壁厚方向温度分布，通过有限元分析，得到柱板式空心墩在日照升温和寒潮降温作用下温度效应。利用数值回归分析法，得到柱板式空心墩墩壁温差梯度拟合函数，以及温度荷载加载计算的简化模式。研究结果显示，外界气温变化对柱板式空心墩板的影响深度只有60 cm 左右，且沿混凝土板厚度方向温度呈非线性变化；日照升温作用下在柱和板过渡段折角处出现较大的拉应力和压应力，寒潮降温作用下，在柱和板过渡段的折角处出现较大的拉应力；温度梯度在柱板式空心墩的板厚方向是按照指数函数形式分布，简化后可采用折线温度荷载模式。