双肢拼合冷弯薄壁型钢箱型截面构件受力性能分析

发布时间：2018-05-05 09:17

本文选题：冷弯薄壁型钢 + 双肢拼合箱型截面构件　；参考：《山东建筑大学》2017年硕士论文

【摘要】：冷弯薄壁型钢C型截面构件弯心与剪心不重合、抗扭能力差,为提高其稳定性和承载能力,本文提出了一种双肢拼合冷弯薄壁型钢构件,通过在两个C型型钢构件中间设置填板,拼合成一种箱型截面形式。为了探讨双肢拼合冷弯薄壁型钢截面构件的受力性能,采用ANSYS有限元软件对拼合构件的弯曲和轴压性能进行了数值模拟分析,探讨了填板设置对拼合构件的破坏模式、极限承载和位移延性等影响,研究表明:1.拼合构件在弯曲受力状态下:拼合构件破坏表现为整体弯曲屈曲和填板之间截面的畸变及局部屈曲的混合模式,未表现出整体的畸变屈曲或弯扭屈曲。(1)填板宽度对拼合构件的受弯性能影响较大,当填板宽度在220mm~340mm范围变化时,随着填板宽度增加,构件的弯曲极限承载力和抗弯刚度呈增大趋势,位移延性随填板宽度的增加而减小。(2)填板间距对拼合构件的受弯承载性能影响也较大,当填板间距在240mm~400mm范围变化时,随着填板间距减小,构件的弯曲极限承载力和抗弯刚度呈增大趋势,位移延性随着填板间距的减小而增大。(3)翼缘宽厚比对拼合构件的影响明显,当构件翼缘宽厚比在35~48范围变化时,随着翼缘宽厚比增大,其受弯极限承载力变小,变小趋势平缓,翼缘宽厚比越大,翼缘上的破坏程度越大,破坏模式由畸变加局部的混合破坏逐渐变为畸变破坏,且翼缘板上的破坏逐渐加剧,位移延性随着翼缘宽厚比的增大而减小。2.拼合构件在轴压受力状态下:拼合构件破坏表现为整体弯曲屈曲和填板之间截面的畸变及局部屈曲的混合模式;同时,构件最先发生腹板的局部屈曲,未表现出整体的畸变屈曲或弯扭屈曲。(1)填板宽度对拼合构件的受压性能影响较大,当填板宽度在210mm~330mm范围变化时,随着填板宽度增加,构件轴压极限承载力和轴压刚度呈增大趋势,位移延性随着填板宽度的增大而增大。(2)填板间距对拼合构件的影响也较大,当填板间距在197mm~356mm范围变化时,随着填板间距的减小,构件轴压极限承载力和轴压刚度呈增大趋势;同时填板间距的变化,只影响构件的破坏程度,不改变构件破坏模式,最终都是腹板破坏,带有一定的翼缘破坏。位移延性随着填板间距的减小而增大。(3)翼缘宽厚比对拼合构件的影响明显,当翼缘宽厚比在35~48范围变化时,随着翼缘宽厚比增大,其轴压极限承载力呈增大趋势,翼缘宽厚比越大,构件破坏时翼缘的破坏程度也越大,但不改变构件的破坏模式,位移延性随着翼缘宽厚比的增大而增大。
[Abstract]:In order to improve the stability and bearing capacity of cold-formed thin-walled steel section C section members, the bending center does not coincide with the shear center and the torsion resistance is poor. In order to improve its stability and bearing capacity, a kind of cold-formed thin-walled steel member with two legs is proposed in this paper. A box-shaped section form is formed by setting fill between two C-type steel members. In order to study the mechanical behavior of cold-formed thin-walled steel section members with two legs, the bending and axial compression behaviors of the composite members were simulated by ANSYS finite element software, and the failure mode of the composite members was discussed. The effects of ultimate bearing capacity and displacement ductility are studied. In the state of bending force, the failure of the jointed member is a mixed mode of the section distortion and local buckling between the whole bending buckling and the filling plate. When the width of the fill plate changes in the range of 220mm~340mm, the width of the fill plate increases with the increase of the width of the fill plate, and the bending behavior of the composite member is greatly affected by the width of the fill plate, which does not show the whole distortion buckling or bending buckling. The ultimate flexural capacity and flexural stiffness of the members tend to increase, and the displacement ductility decreases with the increase of the width of the fill plate.) the spacing of the fill plate has a great influence on the flexural bearing capacity of the composite member. When the spacing of the fill plate changes in the range of 240mm~400mm, the displacement ductility decreases with the increase of the width of the fill plate. The ultimate bearing capacity and flexural stiffness of the members increase with the decrease of the spacing between the fill plates, and the displacement ductility increases with the decrease of the spacing between the fillers. When the flange width to thickness ratio changes in the range of 35 ~ 48, with the increase of the flange width to thickness ratio, the ultimate flexural bearing capacity becomes smaller, the smaller trend is gentle, the greater the flange width to thickness ratio, the greater the damage degree on the flange. The failure mode is changed from distortion and local mixed failure to distortion failure, and the damage on flange plate is gradually aggravated, and the displacement ductility decreases with the increase of flange width to thickness ratio. Under axial compression condition, the failure of jointed member is a mixed mode of the section distortion and local buckling between the whole bending buckling and the filling plate, at the same time, the local buckling of the web is the first occurrence of the member. The width of the fill plate has a great influence on the compression performance of the composite member. When the width of the fill plate changes in the range of 210mm~330mm, the width of the fill plate increases with the width of the fill plate. The ultimate bearing capacity and axial compression stiffness of the members are increasing, and the displacement ductility increases with the width of the fill plate. (2) the spacing of the fill plate has a great influence on the assembly members. When the spacing of the fill plate changes in the range of 197mm~356mm, the displacement ductility decreases with the increase of the spacing of the fill plate. The ultimate bearing capacity and the axial compression stiffness of the members are increasing, and the change of the spacing between the fill plates only affects the failure degree of the members, and does not change the failure mode of the members. Finally, they are all web failure with certain flange failure. The displacement ductility increases with the decrease of the spacing of the fill plate. The influence of flange width to thickness ratio is obvious. When the flange width to thickness ratio changes in the range of 35 ~ 48, the ultimate bearing capacity of the flange increases with the increase of the flange width to thickness ratio. The larger the flange width to thickness ratio is, the greater the flange damage degree is, but the displacement ductility increases with the increase of the flange width thickness ratio, but does not change the failure mode of the member.
【学位授予单位】：山东建筑大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU392.1

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