【作者】 王立福；

【导师】 杨佑发；

【作者基本信息】 重庆大学 ， 工程力学， 2004， 硕士

【摘要】 随着钢板箱形梁在工程中的广泛的应用,畸变效应对其受力性能的影响越来受到工程设计人员的重视。在工程实践中,设置横隔板被认为是减小畸变效应的有效方法。但是,有关横隔板设置的合理密度和位置、在不同的荷载形式和约束条件下横隔板对畸变效应影响的差异等方面的研究还不够充分。因此,继续研究横隔板对钢板箱形梁畸变效应的影响规律,对于工程实践具有重要的指导意义。本文采用荷载分解法将作用于箱形梁的偏心荷载进行分解,得到了畸变、刚性扭转和对称弯曲的分析荷载。利用有限元分析软件建立三维实体模型,分别对两端简支、两端固支和悬臂钢板箱形梁在承受集中和均布荷载时,横隔板对畸变的影响作用进行分析,得到了不同约束和荷载条件下畸变位移和畸变正应力沿梁轴方向的分布规律。通过逐步改变箱梁内横隔板的数量,考查了横隔板的设置密度与畸变的关系;并将畸变的计算结果与相同条件下按刚性扭转、对称弯曲和偏心荷载作用下的计算结果进行了比较分析,得到了反映横隔板密度对畸变效应的影响曲线。在此基础上,提出了偏心荷载作用下钢板箱形梁的简化设计计算方法。通过分析,得到了以下初步的结论:① 横隔板对箱形梁的畸变具有明显的约束作用;畸变程度的大小与横隔板的设置密度有密切的关系;横隔板的设置密度是由畸变效应决定的;② 即使设置了较高密度的横隔板,也无法使畸变效应减小到相对于刚性扭转效应可以忽略的程度;是否考虑畸变的影响会对箱形梁的约束扭转分析产生很大的影响;③ 对于不同的荷载形式和约束条件,横隔板对畸变的影响效果也是不相同的;④ 在横隔板设置处,畸变变形是非常微小的;对于承受集中恒荷载的箱形梁,仅需在荷载作用处设置一道横隔板就可使畸变变形减小到很小的程度。更多还原

【Abstract】 With the wide use, the effect of distortion on the mechanical properties of steel slab box girder is more and more drawn attention by engineers. In engineering practice, the way of install diaphragms is regard as the most effective method to reduce distortion effects. But the research about diaphragm, such as the rational density and position of diaphragm installation, the difference of distortion effect under different boundary conditions and load cases, is very deficient. So it is significative to investigate the influence rule of diaphragm to distortion to project practice.In this paper, the effect of diaphragm density on restraining the distortion of thin-walled steel box girder with rectangle cross section is analyzed based on the finite element method. With different load cases of concentrated load and uniformly distributed load and different boundary conditions of two simply supported ends, two fixed ends and cantilever, the displacement and stress are examined individually and compared with each other under distortion, torsion, bending, and eccentric loads cases. By changing the amount of the diaphragm, the relations between density of diaphragm and distortion effect are investigated. According to the results, variation curves of distortion effect with density of diaphragm under different boundary conditions and load cases are drawn. Based on the analysis results, a simplified design calculation method of steel box girder subjected to eccentric load is proposed. Analysis results indicate that:① Installing amount of diaphragms can effectively reduce the distortion effects.There is a close relation between distortion and density of diaphragms, the density of diaphragm is determined by distortion effects.② Even with a fairly great density of diaphragms, the distortion effects can not be neglected compared with the effects of rigid torsion.③ The effect of diaphragm on distortion are different under different load cases and boundary conditions.④ In the places of diaphragm installation, the deformation is negligible. For box girder subjected to dead force, only one diaphragm at load point can reduce the deformation to a negligible level.更多还原