腹开圆孔工字钢梁的弯—剪承载力相关性研究及应用

【作者】 罗群；

【导师】 周朝阳；

【作者基本信息】 中南大学 ， 结构工程， 2008， 硕士

【摘要】 腹板开孔钢梁便于敷设管道,因而具有降低结构层高、建筑自重和使用能耗等优点,故在工业与民用建筑等工程结构中具有应用前景。目前腹板开孔梁的强度设计方法中,按实腹钢梁进行计算时误差较大,费氏空腹桁架法是一种近似的弹性分析方法且计算过程并不简单,而有限元分析方法虽然精度较高但费时费力。因此,本文从宏观的角度对开孔钢梁的极限承载力进行非线性分析,研究开孔截面弯-剪承载力的相关性以及以此为基础的简化设计方法,为工程设计人员提供方便。本文主要针对腹开圆孔工字钢梁进行分析研究,主要工作和成果如下:首先对腹板开孔钢梁的研究与应用现状进行了综合评述,指出了腹板开孔梁现行设计计算方法存在的问题,说明了简化工字钢梁腹板开孔设计的重要性。根据国产工字型钢型号和常用孔高比,建立了腹开圆孔悬臂简支梁非线性有限元分析模型,可通过调整悬臂梁端集中荷载的大小,获得开孔截面不同的弯-剪组合。基于大量计算,验证了开孔截面纯弯抗力既有计算公式的适用性,给出了开孔截面纯剪抗力表,绘制了开孔截面的弯-剪承载力相关曲线,并经拟合得到了相应的相关方程。对均布荷载作用下腹开圆孔钢梁进行一系列非线性有限元分析,研究了开孔位置、孔高比和截面尺寸对承载力的影响规律,并验证了基于开孔截面弯-剪承载力相关性对均布荷载作用下钢梁腹部开孔进行简化设计的可行性。本文的分析方法和得出的结论,对腹板开孔钢梁的设计和研究有一定的参考价值。更多还原

【Abstract】 Steel beams with web opening have a apply prospect in industrial and civil buildings because they have the adavantage of decreasing storey, self-gravity and energy consumption due to permitting the pipeline through the beam. In the current strength design method for steel beam with web opening, one based on solid-web steel beam used has great errors and Virenteel Mechanism method is still a similar elastic calculation, whose calculation process is not simple. Although accuracy of finite element analysis is good, it cost time and effort. Thus, non-linear FEA were done for limit load capacioty of steel beam circle web opening from macro point to analysis the moment-shear interaction of opening section and simplified design method for designers’ convenience in project. This paper mainly is for the analysis of steel I beam with circle web opening and the main work and achievement are as follow:Firstly, analysis is done on current design and calculation way for steel beam with web opening and there are some problems in these methods. So it is important to put forward a simple design method for steel beam with web opening.Secondly, On the basis of domestic I-beam and the common hole diameter-section depth ratio, cantilever-simple steel I beam with one circle web opening is modeled in finite element analysis and different moment-shear combination is got through adjusting the force at the end of cantilever. Based on a lot of calculation, the application of existing formula for calculating pure flexure resistance capacity is verified and table of pure shear resistance capacity is given. Meanwhile, Moment-shear interaction curve is plotted and then equation is got from fitting result.Thirdly, series of nonlinear finite element analysis is carried on steel beam with circle web opening under distributed load to analysis the impact regulation of web opening position, hole diameter-section depth ratio and section size on load capacity. Furthermore, it is verified that the moment-shear interaction design equation is feasible for the simple design of steel I beam under distributed load.The analysis and conclusion from the paper is valuable for project design and further study on steel beam with web opening.更多还原