为研究大曲率主管的圆钢管X型节点轴压性能,采用数值模拟方法对96个不同支、主管外径比β、主管径厚比2γ和主管曲率半径R的圆钢管节点进行有限元参数分析。有限元参数分析结果表明:支、主管外径比β对节点的破坏模式影响较大;曲率半径...为研究大曲率主管的圆钢管X型节点轴压性能,采用数值模拟方法对96个不同支、主管外径比β、主管径厚比2γ和主管曲率半径R的圆钢管节点进行有限元参数分析。有限元参数分析结果表明:支、主管外径比β对节点的破坏模式影响较大;曲率半径R对节点破坏模式影响较小。小β值节点主管出现局部凹陷之后产生一定薄膜效应导致承载力出现一定回升;大β值节点试件主管仅出现椭圆化变形无承载力回升现象。当β=0.8时,随着曲率变化节点极限承载力变化较小。当β=0.2、0.4和0.6时,主管曲率半径大于12倍主管直径时,极限承载力变化较小;主管曲率半径小于12倍主管直径时,极限承载力随曲率增大而有所提高。对于相同的主管径厚比2γ,主管曲率半径大于12倍主管直径时,极限承载力变化较小;主管曲率半径小于12倍主管直径时,极限承载力随曲率增大而有所提高。在欧洲钢结构规范(Eurocode3 Design of Steel Structures)中的主管平直的圆钢管X型节点极限承载力计算公式的基础上,采用乘以修正系数的方式拟合出大曲率主管的圆钢管X型节点轴压承载力计算公式,为该类节点的设计提供参考。展开更多
The details of a research study of galvanized steel tube under web crippling were presented. A total of 48 galvanized steel square hollow sections with different boundary conditions, loading conditions, bearing length...The details of a research study of galvanized steel tube under web crippling were presented. A total of 48 galvanized steel square hollow sections with different boundary conditions, loading conditions, bearing lengths and web slenderness were tested. The experimental scheme, failure modes, load-displacement curves and strain intensity distribution curves were also presented. The investigation was focused on the effects of loading condition, bearing length and slenderness on web crippling ultimate capacity, initial compressive stiffness and ductility of galvanized steel tube. The results show that web crippling ultimate capacity increases linearly with the increase of the bearing length under EOF and IOF loading condition. In the end-flange and ITF loading conditions, strain intensity of the centerline of web reaches the peak and decreases progressively from central web to flanges. Finite element models were developed to numerically simulate the tests in terms of failure modes and ultimate capacity. Web crippling strength of galvanized steel tube increases linearly with the increase of the ratio of the bearing length to web thickness and decrease of web slenderness. The effect of ratio of galvanized layer thickness to web thickness on web crippling strength is small. Based on the results of the parametric study, a number of calculation formulas proposed in this work can be successfully employed as a design rule for predicting web crippling ultimate capacity of galvanized steel tube under four loading and boundary conditions.展开更多
文摘为研究大曲率主管的圆钢管X型节点轴压性能,采用数值模拟方法对96个不同支、主管外径比β、主管径厚比2γ和主管曲率半径R的圆钢管节点进行有限元参数分析。有限元参数分析结果表明:支、主管外径比β对节点的破坏模式影响较大;曲率半径R对节点破坏模式影响较小。小β值节点主管出现局部凹陷之后产生一定薄膜效应导致承载力出现一定回升;大β值节点试件主管仅出现椭圆化变形无承载力回升现象。当β=0.8时,随着曲率变化节点极限承载力变化较小。当β=0.2、0.4和0.6时,主管曲率半径大于12倍主管直径时,极限承载力变化较小;主管曲率半径小于12倍主管直径时,极限承载力随曲率增大而有所提高。对于相同的主管径厚比2γ,主管曲率半径大于12倍主管直径时,极限承载力变化较小;主管曲率半径小于12倍主管直径时,极限承载力随曲率增大而有所提高。在欧洲钢结构规范(Eurocode3 Design of Steel Structures)中的主管平直的圆钢管X型节点极限承载力计算公式的基础上,采用乘以修正系数的方式拟合出大曲率主管的圆钢管X型节点轴压承载力计算公式,为该类节点的设计提供参考。
基金Projects(51278209,51378077,51478047)supported by the National Natural Science Foundation of ChinaProject(ZQN-PY110)supported by Promotion Program for Young and Middle-aged Teacher in Science and Technology Research of Huaqiao University,China+1 种基金Project(2014FJ-NCET-ZR03)supported by Program for New Century Excellent Talents in Fujian Province University,ChinaProject(JA13005)supported by Incubation Program for Excellent Young Science and Technology Talents in Fujian Province Universities,China
文摘The details of a research study of galvanized steel tube under web crippling were presented. A total of 48 galvanized steel square hollow sections with different boundary conditions, loading conditions, bearing lengths and web slenderness were tested. The experimental scheme, failure modes, load-displacement curves and strain intensity distribution curves were also presented. The investigation was focused on the effects of loading condition, bearing length and slenderness on web crippling ultimate capacity, initial compressive stiffness and ductility of galvanized steel tube. The results show that web crippling ultimate capacity increases linearly with the increase of the bearing length under EOF and IOF loading condition. In the end-flange and ITF loading conditions, strain intensity of the centerline of web reaches the peak and decreases progressively from central web to flanges. Finite element models were developed to numerically simulate the tests in terms of failure modes and ultimate capacity. Web crippling strength of galvanized steel tube increases linearly with the increase of the ratio of the bearing length to web thickness and decrease of web slenderness. The effect of ratio of galvanized layer thickness to web thickness on web crippling strength is small. Based on the results of the parametric study, a number of calculation formulas proposed in this work can be successfully employed as a design rule for predicting web crippling ultimate capacity of galvanized steel tube under four loading and boundary conditions.
