CN115030346A - 一种构造简易的热轧工字钢防屈曲支撑 - Google Patents

一种构造简易的热轧工字钢防屈曲支撑 Download PDF

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CN115030346A
CN115030346A CN202210820378.0A CN202210820378A CN115030346A CN 115030346 A CN115030346 A CN 115030346A CN 202210820378 A CN202210820378 A CN 202210820378A CN 115030346 A CN115030346 A CN 115030346A
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steel
shaft pin
hot rolled
core rod
restrained brace
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陈友泉
雷文江
王亚宇
吴华英
常竞
江涛
王立安
张更生
刘金兰
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Hangxiao Steel Structure Jiangxi Co ltd
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    • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
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    • E04B1/24—Structures comprising elongated load-supporting parts, e.g. columns, girders, skeletons the supporting parts consisting of metal
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    • E04B1/18—Structures comprising elongated load-supporting parts, e.g. columns, girders, skeletons
    • E04B1/24—Structures comprising elongated load-supporting parts, e.g. columns, girders, skeletons the supporting parts consisting of metal
    • E04B2001/2466—Details of the elongated load-supporting parts
    • E—FIXED CONSTRUCTIONS
    • E04—BUILDING
    • E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
    • E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
    • E04B1/38—Connections for building structures in general
    • E04B1/58—Connections for building structures in general of bar-shaped building elements
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Abstract

本发明专利公开一种构造简易的热轧工字钢防屈曲支撑,由低屈服强度高延性的热轧工字钢作为内核芯杆件承受轴向力作用,外套方形钢管不承受轴向力作用，仅用于约束内核芯工字钢的弯曲变形,在核芯工字钢腹板二侧对称焊接约束板,依靠约束板顶住外套的方形钢管可约束内核芯工字钢绕弱轴的弯曲变形。按照受压杆件欧拉临界应力大于2倍的钢材屈服强度计算设置约束板的间距，可确保本发明热轧工字钢防屈曲支撑在地震反复拉和压作用下具有良好的耗能性能。本发明或避免了通常防屈曲支撑极为复杂的构造方式，或避免了通常防屈曲支撑在狭窄钢管内灌注混凝土一类材料的困难施工方法，因而制作简单、构件轻巧、施工方便，具有很好的经济效益，值得推广应用。

Description

一种构造简易的热轧工字钢防屈曲支撑
技术领域
本发明涉及建筑技术领域，具体来说，就是一种用于抗地震作用的支撑耗能构件。
背景技术
本发明专利技术提供了一种构造简易的热轧工字钢防屈曲支撑，用于多高层钢框架+支撑结构体系中。
多高层钢框架+支撑结构体系依靠支撑抵抗大部分地震力作用，在地震力往复作用下，支撑受压时会产生屈曲失稳，故需要设计防屈曲支撑来抵抗地震力作用，且希望通过支撑的大变形来消耗地震能量，达到保护钢框架主体结构不受地震力破坏之目的，因此，设计者致力于设计各种构造复杂的防屈曲支撑，以实现支撑变形复位的耗能性能，有很多的防屈曲支撑采用在内核芯构件与外约束钢管之间灌注混凝土或其他材料办法来防止内核芯构件不会受压屈曲失稳，这些方式使得防屈曲支撑构造极为复杂或笨重，制作难度大，造价高，施工极不方便。
本发明专利根据受压构件的屈曲失稳力学原理及构件抗震耗能滞迴曲线原理，采用低屈服强度高延性的热轧工字钢作为内核芯杆件，对内核芯构件工字钢绕腹板弯曲的弱轴方向设置约束板，利用约束板顶靠外套的方形钢管，从而约束住内核芯工字钢构件不会发生弯曲失稳，此外，采用的普通型热轧工字钢，其翼缘的宽厚比与腹板的高厚比均很小，翼缘和腹板的临界屈曲应力远大于钢材的屈服强度，故不会发生局部屈曲，由此可避免通常防屈曲支撑的复杂构造方式，也可避免内灌混凝土等材料，得到构造简单，轻便高效，便于制作和安装的防屈曲支撑结构，具有显著的经济效益。
发明内容
本发明是一种构造简易的热轧工字钢防屈曲支撑设计，发明内容主要是：
(1)针对多高层钢结构框架体系，设计一种热轧工字钢支撑，外套以方形钢管防止其弯曲失稳，在小地震作用下支撑处于弹性变形状态，在大地震作用下钢材进入屈服状态，热轧工字钢件的翼缘宽厚比和腹板高厚比足够小，不会发生局部屈曲，确保支撑具有良好的抗震耗能性能。
(2)热轧工字钢杆件为核芯受轴向力作用，在其弱轴方向设置约束板，以约束板的间距作为该杆件弱轴方向的计算长度来计算其欧拉临界力，该欧拉临界应力大于2倍的屈服应力，确保钢支撑在压力作用时可屈服但不会发生弱轴方向弯曲失稳，其强轴方向直接受外套的方钢管约束，不会发生强轴方向的弯曲失稳。外套的方钢管只受自相平衡的横向力作用不受轴向力作用，故不会发生弯曲失稳。
(3)设计支撑的轴销连接构造形式，保证支撑的连接构造不出现强度破坏。
附图说明
为了更清楚地说明本发明的技术方案,下面对实施例描述中所需要使用的附图作简单介绍，显然，对于本领域普通技术人员而言，在不付出创造性劳动的前提下,还可以根据这些附图获得其它的附图。
图1是本发明实施例提供的防屈曲支撑核芯杆件构造图。
图2是本发明实施例提供的屈曲支撑外套钢管构造图。
附图标记：1-核芯杆，2-方钢管，3-约束板，4-端头板，5-上轴销连接板，6-下轴销连接板，7-轴销孔，8-加劲肋，9-轴销
具体实施方式
【1】本发明的图示为示意性的，图示主要为说明技术含义，均没有按制图比例绘制，此处进行具体实施描述给出了各种具体组成部件的规格尺寸，但完全可以用其他类似规格与尺寸替换，不应以此作为对本发明的保护范围构成限制。
【2】实施例：为了使本技术领域的人员更好地理解本发明实施例中的技术方案，并使本发明实施例的上述目的、技术特征、构造方式能具体明确，下面结合附图对本发明实施例中的技术方案作进一步详细的说明。
1.请参考附图1和附图2，显示了本发明的设计，实施例设计的构造等具体尺寸主要取决于防屈曲支撑的核芯杆1为普通热轧I28b，长度为6200mm。方钢管2规格为口306×10，长度为6110mm,本实施例吊装的支撑长度为7224mm。
2.本发明设计的轴销9直径为62mm，长度为250mm,端头板4规格-42×350×350，约束板3规格为-14×135×251,加劲肋8规格为-14×134×134。上轴销连接板5规格为-42×192×630,下轴销连接板6规格为-42×192×310，并在上、下轴销连接板上开轴销孔7直径为82.5mm，
3.除轴销9材料用40号钢，核芯杆1钢材为Q235之外，其它所有构件与配件均采用Q355钢材。
4.支撑稳定性计算：按照约束板3顶住外套方钢管2的间距作为核心杆1绕弱轴方向的压杆欧拉临界力计算长度Ly，本实例取Ly＝1500mm，欧拉临界力为
Figure BDA0003744057550000041
欧拉临界应力为
σcj＝Pcj/A＝3287000/6097＝539pam>>2fy＝2X235＝470pam
稳定临界应力远大于2倍的钢材屈服强度，故可保证支撑屈服而不失稳，核芯杆1的强轴方向直接有外套方钢管2约束，可屈服而不失稳，核芯杆1的翼缘弹性临界屈曲应力为
Figure BDA0003744057550000042
核芯杆1的腹板弹性临界屈曲应力为
Figure BDA0003744057550000043
(注：实际杆件会有初始缺陷，其实际的稳定临界应力会低于上述理论计算的失稳临界应力，应适当折减，但本实例的稳定应力计算值远大于其理论值，故可确保不会失稳。)
外套的方钢管2只受平衡的横向力作用，可在轴向自由滑移不受轴向力作用，故不会有稳定问题需要考虑。
5.防屈曲支撑杆件的装配顺序：将一块端头板4采用T型坡口对接焊与核芯杆1的端头连接→将一对加劲肋8焊接在核芯杆1的腹板和端头板4上→按核芯杆1绕弱轴方向弯曲稳定计算的间距Ly布置约束板3并与核芯杆1的翼缘及腹板双面角焊缝连接→在核芯杆1上外套方钢管2，并在其端头处与端头板4焊缝连接→在核芯杆1的另一头同样方式焊接端头板4与加劲肋8→将一对上轴销连接板5间隔84mm采用T型坡口对接焊接在端头板4上→将一对下轴销连接板6同样方式焊接在另一端头板4上。
6.现场安装顺序：先将上轴销连接板5夹住钢框架的节点连接板，并一直上移到底→移动支撑杆将下轴销连接板6对准钢框架的节点连接板→将支撑杆往下回移对准轴销孔7，插入上端轴销9→插入下端轴销9，完成安装
7.本实施例证明本发明技术制作简单，安装轻巧方便，也便于支撑损坏后的替换安装，符合理想的装配式建筑方式，具有显著的经济效益和社会效益，值得推广应用。

Claims (6)

1.一种构造简易的热轧工字钢防屈曲支撑,其特征在于：采用低屈服强度高延性的热轧工字钢作为支撑核芯杆(1)，外套方钢管(2)，在所述核芯杆(1)的腹板二侧按计算确定的间隔对称地焊接约束板(3)，所述方钢管(2)，与所述核芯杆(1)的翼缘及所述约束板(3)之间的间隙均为2.0～3.0mm，所述核芯杆(1)的二端头各焊接一块端头板(4)，所述内核芯杆(1)的一端头板(4)焊接一对上轴销连接板(5)，另一端头板(4)焊接下轴销连接板(6)，所述上轴销连接板(5)和下轴销连接板(6)上均开有轴销孔(7)，通过轴销(9)将热轧工字钢防屈曲支撑连接在钢框架结构体系中。
2.根据权利要求1所述的一种构造简易的热轧工字钢防屈曲支撑，其特征在于：所述方钢管(2)的长度比所述核芯杆(1)的长度短80mm以上，所述方钢管(2)的一个端头与所述内核芯杆(1)的端头板(4)焊接固定，另一个端头不可焊接固定，所述方钢管(2)可自由伸缩滑移。
3.根据权利要求1所述的一种构造简易的热轧工字钢防屈曲支撑，其特征在于：所述轴销(9)的直径不宜小于所述核芯杆(1)的截面积的开平方根的0.8倍，所述轴销孔(7)的孔径比所述轴销(9)的直径大2.5mm。
4.根据权利要求1所述的一种构造简易的热轧工字钢防屈曲支撑，其特征在于：所述端头板(4)的厚度宜不小于所述轴销(9)直径的0.67倍，且钢材需要有Z向性能，其尺寸比所述方钢管(2)截面尺寸大40mm～50mm。
5.根据权利要求1所述的一种构造简易的热轧工字钢防屈曲支撑，其特征在于：所述上轴销连接板(5)的规格宜为-0.67d×(3d+6)×5d(mm)，所述下轴销连接板(6)的规格宜为-0.67d×(3d+6)×(10d+10)(mm)，d为所述轴销(9)的直径值。
6.根据权利要求1所述的一种构造简易的热轧工字钢防屈曲支撑，其特征在于：在所述核芯杆(1)的二端头处的腹板二侧对称焊接一对加劲肋(8)并与所述端头板(4)相连焊接。
CN202210820378.0A 2022-07-13 2022-07-13 一种构造简易的热轧工字钢防屈曲支撑 Pending CN115030346A (zh)

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