不同角度荷载作用下椭圆形钢管混凝土桥墩压弯性能研究

Research on the Combined Compressive and Flexural Performance of Elliptic Concrete-filled Steel Tube Pier under Different Angle Loads

椭圆形钢管混凝土桥墩的流线外形可以有效降低水流等的作用,但是其截面特性较为复杂,尤其是当荷载沿非对称轴方向作用时,容易发生扭曲而降低强度。为了研究不同角度荷载作用下椭圆形钢管混凝土桥墩的压弯性能,本研究采用数值分析软件,建立并通过试验验证了可以精确模拟圆形钢管混凝土桥墩力学性能的数值分析模型。进一步地,利用模型分析了0°~90°不同角度加载时椭圆形钢管混凝土桥墩的压弯性能,分析了不同荷载角度对承载性能的影响规律。结果表明,随着加载角度从0°增加到30°、60°、90°,椭圆形钢管混凝土桥墩极限压弯承载力分别下降了5.38%、27.18%、37.03%;初始刚度随着荷载作用角度的增加而降低,屈服位移和极限位移随着水平荷载作用角度的增加而有所上升。本研究的结果可为椭圆形钢管混凝土桥墩的设计提供借鉴。

The elliptical concrete-filled steel tube(CFST)bridge pier can effectively reduce the action of water flow,but its cross section characteristics are complicated,especially when the load acts along the asymmetric axis,it is easy to distort and reduce the strength.In order to study the elliptical CFST bridge piers under different angle of load performance,in this paper,the numerical analysis software is used to set up the numerical model and verify the results by test which can accurately simulate the mechanical properties.Further,using the model,the bending performance of the lliptical CFST bridge piers under O°~go°angle of loading is analyzed.The influence of different load angles on bearing capacity is analyzed.The results show that with the increase of loading angle from 0°to 30°,60°and 90°,the ultimate bending capacity of elliptical CFST bridge pier decreases by 5.38%,27.18%and 37.03%,respectively.The initial stiffness decreases with the increase of load angle,while the yield displacement and ultimate displacement increase with the increase of horizontal load angle.The research results of this paper can provide reference for the design of elliptical CFST bridge pier.