钢结构槽型肋矩形加劲板稳定性能分析

发布时间：2018-04-18 21:00

本文选题：稳定理论 + 钢结构矩形加劲板　；参考：《山东大学》2017年硕士论文

【摘要】：钢结构矩形加劲板采用扁钢肋、T型钢肋或角钢肋后,在承受面部侧压、纵压轴压等荷载时易发生整体屈曲或局部屈曲。实际工程经验表明,宽翼缘形式的国标普通槽钢加劲肋由于其优越的截面性能以及与壁板焊接的贴合性,更具有推广价值。槽钢肋薄壁矩形加劲板结构在工业建筑、桥梁工程和船舶工业等领域有广泛应用。本文在对T型、L型和球头型等对称和非对称截面形式加劲肋的研究基础上,重点分析了槽型钢肋矩形加劲板的稳定性能,探讨了槽钢肋加劲板的极限承载能力。首先,研究了槽钢肋矩形加劲板在荷载组合作用下复杂的失稳行为,包括:槽钢肋矩形加劲板的整体屈曲、槽钢肋间矩形板的局部屈曲和槽钢加劲肋的屈曲。认为在高腹板加劲肋承受偏心受压较大时,加劲肋腹板侧倾行为对加劲板屈曲应力影响较为明显,为后续研究槽钢肋矩形板的屈曲行为和失效问题提供了基础。其次,对单根槽钢加劲肋矩形板的腹板弯扭屈曲行为进行了研究。取有效宽度内单根肋的加劲板为研究对象,建立了槽钢肋与加劲板组合体简化的受力模型。假定在矩形板屈曲之后槽钢肋对其加劲约束作用完全丧失,随着板内纵向压应力增加到屈曲应力的过程中,这种约束作用以抛物线形式衰减至忽略不计。并考虑了肋的腹板侧倾行为对矩形板屈曲行为的影响,求出了在面压和纵向轴压荷载组合作用下槽钢肋矩形板的控制方程和近似屈曲应力。不同侧向荷载对组合作用下加劲板的屈曲性能影响显著,在构件长细比较大时,负压作用下由于槽钢加劲作用加劲板的临界屈曲应力会有一定程度的增大。最后,对多根纵向槽钢肋矩形加劲板的稳定性能进行了分析。采用Abaqus有限元分析软件建立了在面压和纵向轴压荷载组合作用下的多肋板受力模型,分别分析了槽钢肋加劲板体的屈曲行为和考虑初始缺陷的静态后屈曲行为。在保证矩形板槽钢加劲肋端部不发生过于明显局部屈服的情况下,发现槽钢加劲肋腹板屈服区(Yield Zone)开展到一定截面高度时,加劲板丧失承载能力并整体发生较大变形。本文认为槽钢加劲肋沿腹板截面屈服的高度可以客观地评价加劲板的极限承载能力,建议取加劲肋截面腹板高度1/2位置。通过控制挠跨比限制矩形加劲板的在面压和轴压组合作用下发生的法向位移,以保证加劲板的正常使用性能。
[Abstract]:After the rectangular stiffened plate of steel structure adopts flat steel rib T-section rib or angle steel rib, it is easy to take place global buckling or local buckling under the load of face lateral pressure and longitudinal compression axial compression.The practical engineering experience shows that the national standard stiffening rib with wide flange form is worth popularizing because of its superior cross-section performance and the compatibility with the wall plate welding.Thin-walled rectangular stiffened plate with channel ribs is widely used in industrial construction, bridge engineering and ship industry.In this paper, based on the research on the stiffening ribs of T type, L type and spherical type, the stability of rectangular stiffened plates with grooved steel ribs is emphatically analyzed, and the ultimate bearing capacity of stiffened plates of channel steel ribs is discussed.Firstly, the complex buckling behavior of rectangular stiffened plates with channel ribs under load combination is studied, including the global buckling of rectangular stiffened plates with channel ribs, the local buckling of rectangular stiffened plates between ribs and the buckling of stiffened ribs of channel steel.It is considered that when the high web stiffener is subjected to greater eccentric compression, the roll behavior of the stiffened rib web has a more obvious effect on the buckling stress of the stiffened plate, which provides a basis for further study on the buckling behavior and failure problem of the channel steel ribbed rectangular plate.Secondly, the bending and torsional buckling behavior of a single stiffened rib rectangular plate is studied.Taking the stiffened plate with one rib in the effective width as the research object, the simplified force model of the stiffened plate combined with the channel rib is established.It is assumed that after buckling of rectangular plate the stiffening constraint of the channel rib is completely lost and with the increase of the longitudinal compressive stress to the buckling stress in the plate the constraint decreases in the form of parabola to neglect.Considering the influence of the web roll behavior of ribs on the buckling behavior of rectangular plates, the governing equation and the approximate buckling stress of channel steel ribbed rectangular plates under the combination of plane pressure and longitudinal axial compression are obtained.Different lateral loads have a significant effect on the buckling behavior of stiffened plates under the combined action. The critical buckling stress of stiffened plates under negative pressure will increase to a certain extent when the members are larger in length and fineness.Finally, the stability of rectangular stiffened plates with longitudinal ribs is analyzed.The finite element analysis software Abaqus is used to establish the stress model of multi-ribbed slab under the combination of plane pressure and longitudinal axial compression. The buckling behavior of stiffened slab and static post-buckling behavior considering initial defects are analyzed respectively.In order to ensure that the stiffening rib end of rectangular plate does not produce obvious local yield, it is found that when the yield zone of stiffened ribbed rib reaches a certain section height, the stiffening plate loses its bearing capacity and produces a large deformation as a whole.This paper holds that the yield height of stiffener along the web section of channel steel can objectively evaluate the ultimate bearing capacity of stiffened plate. It is suggested that the height of web of stiffened rib section should be taken at 1 / 2 position.The normal displacement of rectangular stiffened plate under the combination of surface pressure and axial pressure is limited by controlling the ratio of deflection to span to ensure the normal service performance of stiffened plate.
【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU391

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