PC箱梁与钢桁架组合加劲梁斜拉桥的刚度与稳定分析

Stiffness and Stability Analysis of a Cable-stayed Bridge with Hybrid PC-box Girder Stiffed by Steel Truss

探讨预应力混凝土箱梁与钢桁架组合式加劲梁高速铁路斜拉桥的刚度与稳定 ,与无钢桁架PC箱梁相比 ,跨径 4 88m大跨度铁路斜拉桥的活载挠度与跨径之比从 1/ 4 2 6降低到 1/777,最小整体弹性稳定系数为 11.9。PC箱梁与钢桁架组合式加劲梁有效地提高了斜拉桥刚度和稳定 ,是大跨度铁路和公铁两用斜拉桥的合理结构形式。

The stiffness and stability of a high speed railway cable stayed bridge with hybrid prestressed concrete box girder stiffed by steel truss are discussed. Comparing to the bridge with a same PC girder without steel truss, the ratio of the maximum deflection of a cable stayed bridge with a 488 m span under high\|speed railway load and the span is reduced from 1/426 to 1/777, the minimum safety coefficient of elastic stability is 11.9. The hybrid girder increases the stiffness and stability of a cable stayed bridge, the structure is reasonable for large span cable stayed bridge with railway and highway.