曲线连续箱梁桥日照温度效应分析

发布时间：2019-05-29 02:04

【摘要】：近年来,我国城市化建设的快速发展,交通运输行业的加速跟进,曲线梁桥能很好的适应地形地貌特征,且造型优美而在高速公路建设和城市互通立交建设中广泛应用。曲线梁桥,顾名思义,平面线形为某种曲线的桥梁。其受力特性较直线梁桥更为复杂,在动恒载作用下产生弯扭耦合现象,增大桥梁竖向挠度。自然条件中的曲线梁桥无时不刻受到周围环境温度的影响。由于混凝土导热性能差,从而在温度荷载作用下产生约束性质的温差应力。这种温差应力有时会达到与动载应力相同的数量级,在工程设计中无法忽略。本文将从理论上论证推导曲线梁作用日照温度梯度荷载而产生的温差应力及变形计算式。建立有限元数学模型,详细计算分析三跨双室连续曲线箱形梁桥的温度效应问题。具体工作如下:建立Midas梁单元模型,日照温度梯度荷载按照我国公路桥梁规范加载方式加载,分别计算不同曲率半径、不同边中跨比以及不同支承形式下的三跨双室曲线箱形梁桥温度效应问题。分析归纳并总结计算结果,得出结论。建立Midas/FEA实体单元模型,分析计算不同曲率半径的纵向温度应力和横向温度应力,找出最大拉压应力分布位置,为工程设计计算提供帮助。将计算结果与梁单元模型计算结果相互对比分析得出结论。以曲线桥平面曲线圆心为参考,考虑混凝土自重荷载和日照温度梯度荷载双重作用下内外侧支座反力分布规律,得出结论,为曲线桥梁设计提供数据参考。
[Abstract]:In recent years, with the rapid development of urbanization and the acceleration of transportation industry in China, curved beam bridges can adapt to the topographic and geomorphological characteristics, and the shape is beautiful, so it is widely used in highway construction and urban interchange construction. Curved beam bridge, as the name implies, the plane alignment is a kind of curved bridge. The mechanical characteristics of the bridge are more complex than those of the linear beam bridge, and the bending and torsional coupling phenomenon is produced under the action of dynamic and constant load, which increases the vertical deflection of the bridge. The curved beam bridge in natural conditions is affected by the temperature of the surrounding environment all the time. Because of the poor thermal conductivity of concrete, the temperature difference stress of constraint property is produced under the action of temperature load. This kind of temperature difference stress can sometimes reach the same order of magnitude as the dynamic load stress, which can not be ignored in engineering design. In this paper, the formulas for calculating the temperature difference stress and deformation caused by sunshine temperature gradient load of curved beams are theoretically demonstrated and deduced. The finite element mathematical model is established, and the temperature effect of three-span and two-chamber continuous curved box girder bridge is calculated and analyzed in detail. The concrete work is as follows: the Midas beam element model is established, and the sunshine temperature gradient load is loaded according to the loading mode of highway bridge code in our country, and the different curvature radii are calculated respectively. Temperature effect of three-span double-chamber curved box girder bridge with different side span ratio and different supporting forms. The calculation results are analyzed and summarized, and the conclusions are drawn. The Midas/FEA solid element model is established, the longitudinal temperature stress and transverse temperature stress with different curvature radii are analyzed and calculated, and the maximum tension and compression stress distribution position is found out, which is helpful for engineering design and calculation. The calculated results are compared with those of the beam element model. Taking the center of plane curve of curved bridge as reference, considering the distribution law of reaction force of inner and outer supports under the dual action of concrete weight load and sunshine temperature gradient load, it is concluded that it can provide data reference for the design of curved bridge.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U441.5

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