脱粘对桁架式钢管混凝土拱肋动力性能的影响

为了解脱粘对桁架式钢管混凝土拱肋动力性能的影响,基于完全脱粘假设选择合理连接单元,运用ANSYS软件建立了总溪河大桥桁架式主拱肋脱粘与完全粘结模型,分析了在全跨、双侧拱脚、单侧拱脚和跨中拱肋脱粘的情况下主拱肋的动力特性。计算结果表明,在全跨范围脱粘状态下,前五阶频率有较明显的下降,其中第三阶下降达27.37%;不同位置脱粘对面内弯曲频率的影响大于对面外弯曲频率的影响,但对一阶扭转频率影响不大;不同位置脱粘对各阶频率的影响是,双侧拱脚脱粘的影响大于单侧拱脚脱粘的影响,单侧拱脚脱粘的影响大于跨中拱肋脱粘的影响。

Effect of debonding on dynamic characteristics of trussed concrete-filled steel tubular arch rib

In order to know about that debonding has impacted on the dynamic property of concrete filled steel tube truss rib, based on complete debonding hypothesis, the reasonable finite element applying ANSYS software is chosen, and the complete debonding model and the truss type main arch rib bonding model of the Zongxi river bridge is established. This paper analyzed dynamic characteristics of the main arch rib in all across, double side arch foot, unilateral arch foot, the middle of arch rib under the condition of complete debonding. The analysis shows that the first five fundamental frequency decline significantly in the whole span of debonding state and the third-order falls by 27%. The impact of the debond in different locations is greater to surface inside bend fundamental frequency than surface outside. The influence of the first order torsional fundamental frequency is small. The impact of double side arch foot debonding is greater than single side, which is greater than the middle of arch rib.