装配式钢桁-混凝土组合连续刚构桥的预制桥道板安装过程有限元模拟方法

发布时间：2018-05-24 08:40

本文选题：钢桁-混凝土组合连续刚构桥 + 装配施工　；参考：《科学技术与工程》2017年20期

【摘要】：为了掌握装配式钢桁-混凝土组合连续刚构桥施工阶段的受力性能,对预制桥道板安装过程进行了精细化有限元建模方法研究。根据该桥型的构造和施工特点,提出了两种不同的模拟方法。方法一为提出在安装钢桁单元时激活钢桁与桥道板之间的弹性连接,以实现预制桥道板单元分批次安装在变形后的钢桁上;且仅设置SD_x方向刚度值,以此模拟桥道板独自获得预压应力的状态。待全桥桥道板安装及张拉完成后,再将弹性连接方式更换为刚性连接,使之成为组合梁承受后期荷载。方法二为在安装钢桁单元时激活钢桁与桥道板之间钢臂连接单元以实现预制桥道板单元分批次安装在变形后的钢桁上,且释放钢臂连接单元顶端转动及水平约束,以此模拟桥道板独自获得预压应力的状态。待全桥桥道板安装及张拉完成后,再恢复钢臂连接单元顶端的转动和水平约束,使之成为组合梁承受后期荷载。分别用以上两种方法建立了某主跨70 m依托工程的全桥计算模型,对其关键施工阶段进行了仿真模拟分析。计算结果表明:两种计算方法均能精确的模拟预制桥道板安装过程,且两种方法数据吻合较好,可供同类桥梁参考。
[Abstract]:In order to master the mechanical performance of prefabricated steel truss concrete composite continuous rigid frame bridge during construction the detailed finite element modeling method for the installation process of precast track slab was studied. According to the structure and construction characteristics of the bridge, two different simulation methods are proposed. Method one is to activate the elastic connection between the steel truss and the bridge track plate when installing the steel truss element, so that the precast bridge track plate element can be installed on the deformed steel truss in batches, and only the stiffness value of the SD_x direction is set. In this way, the state of preloading stress obtained by the bridge slab alone is simulated. After the installation and tensioning of the whole bridge track plate are completed, the elastic connection mode is replaced by the rigid connection, which makes the composite beam bear the late load. The second method is to activate the steel arm connection unit between the steel truss and the bridge track plate when the steel truss element is installed so that the precast bridge track plate unit can be installed on the deformed steel truss in batches and release the tip rotation and horizontal constraint of the steel arm connection unit. In this way, the state of preloading stress obtained by the bridge slab alone is simulated. After the whole bridge track plate is installed and tensioned, the rotation and horizontal constraint at the top of the steel arm connection unit are restored, which makes the composite beam bear the late load. By using the above two methods, the calculation model of the whole bridge of a 70 m main span supporting project is established, and its key construction stage is simulated and analyzed. The results show that the two methods can accurately simulate the installation process of prefabricated bridge track plates and the data of the two methods are in good agreement with each other, which can be used as a reference for similar bridges.
【作者单位】：重庆交通大学山区桥梁结构与材料教育部工程研究中心;重庆交通大学土木工程学院;
【基金】：国家自然科学基金(51308571) 交通运输部应用基础研究项目(2013 319 814 040) 江西省交通运输厅科技项目(2014Y0007)资助
【分类号】：U448.23

【参考文献】