独斜塔斜拉桥预应力索塔锚固区模型试验研究

Full-Scale Model Test of Pre-stressed Cable-Pylon Anchorage for Single-Oblique-Pylon Cable-Stayed Bridges

为保证厦门马新大桥索塔锚固区安全,根据其小半径环向预应力索塔锚固区、非对称受力的4个重要工作状态(预应力施工、正常使用、单索作用和超载),采用斜向加载,进行了足尺模型试验和空间精细有限元分析.结果表明:计算值与试验结果吻合较好,有效预应力对锚固区受力影响很大,索非对称布置对锚固区受力影响不大;环向预应力锚固区极限承载能力超过1.7倍设计索力荷载,安全可靠.

In order to ensure the safety of cable-pylon anchorage of Maxin Bridge in Xiamen, a full- scale model test under oblique loading and spatial finite element analysis were conducted to analyze the mechanical behavior of the prestressed cable pylon installed with asymmetric cables and embedded with small-radius U shape prestressed system. The complicated anchorage zone was investigated under different service phrases, including prestressing, service, asymmetric cable action, and overloading. The results show that numerical and experimental results have a good agreement, the effective prestress has a significant effect on the behavior of the zone, and the effect of asymmetric cable loading is slight. In addition, the ultimate bearing capacity of the cable-pylon anchorage with hooped prestress system exceeds 1.7 times the design cable load, which verifies its reliability.