屈曲约束支撑―混凝土框架结构新型连接节点研究_图文

1、 同济大学建筑工程系 屈曲约束支撑混凝土框架结构屈曲约束支撑混凝土框架结构新型连接节点研究 李国强教授 王彦博博士 Research Group for Multi-Storey and Tall Steel Buildingsand Fire-resistance of Steel Structures主题研究背景现有的钢支撑-混凝土框架连接节点形式存在的问题及提出的解决方法数值分析承载力梁、柱节点梁上节点设计方法探讨节点板刚度对消能器部件的影响试验研究(方案阶段 总结与展望 Research Group for Multi-Storey and Tall Steel Buildings T

2、ongji University支撑承载力小于150吨时,常采用预埋锚筋节点 梁上锚固节点梁、柱锚固节点 Research Group for Multi-Storey and Tall Steel Buildings Tongji University梁、柱包钢节点Research Group for Multi-Storey and Tall Steel Buildings梁、柱预埋钢骨节点Research Group for Multi-Storey and Tall Steel Buildings-各类节点对比研究背景各类节点对存在的问题承载力常用节点类型优点缺点<150技术成熟

3、经济性好吨预埋锚筋节点施工方便不影响外观承载力小 >150施工方便不够经济吨<500吨外包钢板节点承载力较大影响外观>500吨预埋钢骨钢混凝土节点承载力大不影响外观经济性差施工较麻烦 Research Group for Multi-Storey and Tall Steel Buildings Tongji University 方便施穿箍筋定位浇筑方便施工:穿箍筋、定位、浇筑经济性好、对外观影响小梁上节点梁、柱节点Research Group for Multi-Storey and Tall Steel Buildings数值分析几何模型z为研究该类预埋件节点的受力特性

4、、节点域刚度,采用通用有限元软件ABAUS建立了数值模型。z混凝土柱截面尺寸为560X560,混凝土梁截面尺寸为300X560。节点板厚度为30mm,两侧的加劲肋为厚度为10的钢板。腹板开孔型钢尺寸为 H600X300X16X20。栓钉直径为16mm。 Research Group for Multi-Storey and Tall Steel Buildings Tongji University数值分析网格划分采用C3D8R单元 Research Group for Multi-Storey and Tall Steel Buildings Tongji University数值分析材料本

5、构700钢材400500600(M P a 100200300应力000.050.10.150.20.250.3应变钢材采用Q345,实际屈服强度381MPa,抗拉强度509MPa ,弹性模量212GPa。钢材的应力应变关系曲线采用试验弹模材应力应变关系曲线采用试验测试结果,并转换为真实应力-应变关系。 (1nom nom =+ln(1 nom =+True strain: True stress:Research Group for Multi-Storey and Tall Steel Buildings Tongji University 数值分析材料本构混凝土受压混凝土受拉250030

6、.00 35.00 40.00 45.00 P a 2.503.00 3.50 P a 0005.00 10.00 15.00 20.00 25.00 应力(M 0000.50 1.00 1.50 2.00 应力(M 混凝土采用C40抗压强度40MPa 抗拉强度3MPa 弹性模量325GPa 0.000.0050.010.015应变0.000.00020.00040.00060.00080.001应变 z 混凝土采用C40,抗压强度40MPa,抗拉强度3MPa,弹性模量32.5GPa。混凝土单轴受压与受拉本构关系根据混凝土结构设计规范GB50010-2012附录C规定取值。z 混凝土材料模型使

7、用Abaqus 材料库中提供的Concrete Damaged Plasticity,膨胀角取36°,流动势偏心参数取默认值0.1,混凝土双Research Group for Multi-Storey and Tall Steel Buildings Tongji University向受压强度提高系数取为1.16,表征混凝土破坏面的参数kc取为0.67。 梁、柱节点约束嵌入混凝土Tie约束接触 Research Group for Multi-Storey and Tall Steel BuildingsTongji University 梁上节点嵌入混凝土 接触 Researc

8、h Group for Multi-Storey and Tall Steel Buildings Tongji University位移加载,显式分析 固接 固接 Research Group for Multi-Storey and Tall Steel Buildings Tongji University固接固接 位移加载,显式分析位移加载,显式分析 Research Group for Multi-Storey and Tall Steel Buildings Tongji University数值分析结果承载力 Research Group for Multi-Storey and

9、 Tall Steel Buildings Tongji University梁、柱节点 荷载达到0时荷载达到470kN时 Research Group for Multi-Storey and Tall Steel Buildings Tongji University梁、柱节点 荷载达到999kN时荷载达到1126.8kN时 Research Group for Multi-Storey and Tall Steel Buildings Tongji University梁、柱节点荷载达到1340.6kN时 Research Group for Multi-Storey and Tall

10、Steel Buildings Tongji University梁、柱节点 荷载达到1340.6kN时荷载达到1448kN时 Research Group for Multi-Storey and Tall Steel Buildings Tongji University梁、柱节点 荷载达到16669kN时17954kN延性较好 Research Group for Multi-Storey and Tall Steel BuildingsTongji University 梁、柱节点承载力 屈服承载力,1105.3kN极限承载力,1340.6kN Research Group for M

11、ulti-Storey and Tall Steel Buildings Tongji University数值分析结果变形状态梁、柱节点 z 从左图中可以看出,H型钢预埋件腹板近节点板端拉剪变形显著;z 从右图中可以看出,H型钢近节点板翼缘的中部与混凝土脱开,两边与混凝土接触;H型钢远节点板翼缘的中部向受拉方向突起Research Group for Multi-Storey and Tall Steel BuildingsTongji University 变形。 梁上节点 荷载达到532kN时 Research Group for Multi-Storey and Tall Steel

12、Buildings Tongji University梁上节点 荷载达到962.2kN时荷载达到1228kN时荷载达到9622kN时 Research Group for Multi-Storey and Tall Steel Buildings Tongji University梁上节点 延性较好荷载达到1430kN时荷载达到1922kN时 Research Group for Multi-Storey and Tall Steel BuildingsTongji University梁上节点承载力 屈服承载力,962.2kN极限承载力1430kN 屈服承载力9622kN Research

13、Group for Multi-Storey and Tall Steel Buildings Tongji University数值分析结果变形状态梁、柱节点 z 从左图中可以看出,H型钢近节点板翼缘受拉边缘与混凝土脱开,受压段与混凝土接触;H型钢远节点板翼缘的中部向受拉方向受压段与凝接触;节点板翼缘部向受拉方向突起变形。 Research Group for Multi-Storey and Tall Steel BuildingsTongji University z 从右图可以看出,H型钢预埋件腹板近节点板端拉剪变形显著。 Research Group for Multi-Storey

14、 and Tall Steel Buildings Tongji University数值分析结果设计公式根据AISC-LRFD中“均力法”的设计原理,可以计算出节点板与柱连接产生的水平力H uc与竖向力V uc,节点板与梁连接产生的水平力H ub与竖向力V ub节点板与梁连接产生的水平力。 Research Group for Multi-Storey and Tall Steel Buildings Tongji University数值分析结果设计公式 参数分析,拟合 Research Group for Multi-Storey and Tall Steel Buildings Ton

15、gji University数值分析刚度对屈曲约束支撑刚度的影响 水平力按照侧移刚度分配 Research Group for Multi-Storey and Tall Steel Buildings Tongji University数值分析结果刚度 Research Group for Multi-Storey and Tall Steel Buildings Tongji University 节点板混凝土臂节点整体刚度计算对应屈服承载力时状态支撑角度N/mmN/mm N/mm 对比30°3.68E+06 2.22E+06 1.39E+0630°3.88E+06 2

16、.67E+06 1.58E+0635°1.22E+072.69E+06 2.21E+0640°5.68E+06 2.36E+06 1.67E+0645°9.05E+06 2.28E+06 1.82E+06Research Group for Multi-Storey and Tall Steel BuildingsTongji University刚度计算对应屈服承载力时状态角度节点板混凝土臂节点整体N/mm N/mm N/mm45-整体9.93E+06 2.77E+06 2.17E+0640-整体8.79E+06 3.11E+06 2.30E+06 35-整体7

17、.85E+06 2.93E+06 2.14E+0635-分离 5.39E+06 2.56E+06 1.74E+06 30-分离 6.68E+06 2.75E+06 1.95E+06 Research Group for Multi-Storey and Tall Steel Buildings Tongji University数值分析 刚度 对屈曲约束支撑刚度的影响 水平力按照侧移刚度分配 Tongji University Research Group for Multi-Storey and Tall Steel Buildings and Fire-resistance of Stee

18、l Structures 试验研究 验证数值模型-方案阶段 梁上节点 Tongji University 梁、柱节点 Research Group for Multi-Storey and Tall Steel Buildings and Fire-resistance of Steel Structures 总结与展望 腹板开孔H型钢预埋件的整体受力性能优于锚固式预埋件 节点，通过改变H型钢预埋件的长度、厚度与开孔宽度， 该类型连接的承载力可达1500kN5000kN。 对于150吨500吨位的支撑与混凝土连接，还采用外包钢 板与预埋钢骨两种方式。外包钢板的连接形式通常用于即 有混凝土结构的加固，用钢量相对较大；而预埋钢骨的连 接形式则会造成梁、柱箍筋施工的不便。 腹板开孔H型钢预埋件的连接方式与这两者相比，既保证 了经济性 了经济性，又为施工提供了方便，在150吨500吨位的连 为施 提供了方便 在