斜靠式钢管混凝土拱桥稳定承载力分析及成桥试验

Nonlinear stability analysis and completed bridge test on slanting type CFST arch bridges

采用斜靠拱提高斜靠式钢管混凝土拱桥结构的稳定性,该结构体系的受力性能有待深入探究。结合广东省金山大桥(五跨连续斜靠式钢管混凝土刚架系杆拱桥),研究了斜靠式钢管混凝土拱桥在几何非线性及材料非线性条件下的力学性能、破坏机理及稳定承载力。结果表明:斜靠拱的设置可以显著地改善拱肋的稳定性能,但应保证其承载力与钢管混凝土拱肋匹配,以免在极限荷载作用下首先破坏并导致拱肋整体失稳。针对金山大桥开展了成桥后的静动力试验,试验结果表明,斜靠式钢管混凝土拱桥在静动荷载作用下受力性能良好,结构安全可靠。

Slanting type concrete-filled steel tubular( CFST) arch bridges adopt the slanting arch ribs to improve the stability,leading to a new structural style to be investigated. Combined with the Golden Hill Bridge located in Guangdong province( a five-span slanting type CFST arch bridge),this research has investigated the mechanical behavior,failure mechanism and the stable bearing capacity of the slanting type CFST arch bridges under both geometrical and material nonlinearities using the numerical simulation method. It is found that the slanting arch rib employed in CFST arch bridges could improve the stability significantly,whereas it would buckle locally under the ultimate load due to its poor load carrying capacity of the springing,inducing an overall buckling of the whole arch.The loading test on the Golden Hill Bridge was carried out,and the results indicate that the bridge is satisfactory on both the working performance and mechanical behavior.