【摘要】 为研究全装配式钢桁-混凝土组合连续刚构桥应用于特大跨径时的合理装配工序，揭示不同装配工序对桥梁结构性能的影响，建立了l=386m的装配式组合连续刚构桥有限元模型，模拟了6种不同的钢桁、预制桥面板安装工序以及钢混组合结整时机，以分析比较桥面板与钢桁的装配顺序、钢混焊接结整顺序对于桥梁跨中挠度、钢桁上下弦杆应力以及预应力度的影响。计算结果表明：桥面板与钢桁分节段同步施工时，可减小桥梁的上下弦杆应力和跨中挠度值，并提高刚度。但是同时会降低预应力度；桥道板分段焊接在跨中挠度值和上下弦杆应力方面表现出更好的性能，可以平均减小跨中挠度值29.90%，并平均减小上下弦杆应力35.49%，而且能够有效减小靠近桥墩节段的预应力损失；桥道板与钢桁分多段同步施工，合龙后一次性焊接桥道板不仅能保证预应力损失较小，还能提高全桥刚度，因此可推荐为特大跨全装配式钢桁-混凝土连续刚构桥优化施工装配方案，研究结果可为全装配式钢混组合梁桥推广应用提供技术参考。更多还原

【Abstract】 In order to study the reasonable assembly process of fully assembled steel truss-concrete composite continuous rigid frame bridges when applied to super large spans, and to reveal the impact of different assembly processes on the performance of bridge structures, a finite element model of a prefabricated composite continuous rigid frame bridge with l=386m was established, and six different installation processes for steel trusses, prefabricated bridge decks, and the timing of steel-concrete composite construction were simulated, so as to analyze and compare the influence of the assembly sequence of bridge deck and steel truss as well as the welding and assembly sequence of steel concrete on the mid-span deflection of the bridge, the stress and the prestressing force of the upper and lower chords of the steel truss. The calculation results indicate that when the bridge deck and steel truss are being constructed in segments simultaneously, the stress and mid-span deflection values of the upper and lower chords of the bridge can be reduced, while the stiffness can be increased. However, this assembly method reduces the degree of prestressing at the same time; when the bridge deck is welded segment by segment, better performance in terms of reducing deflection at mid-span and the stress on the upper and lower chord members is achieved. This method can reduce the average deflection at mid-span by 29.90%, average stress on the upper and lower chords by 35.49%, and effectively reduce prestress loss near the bridge pier segments; Finally, multi-segment synchronous construction of the bridge deck and steel truss, followed by one-time welding of the bridge deck after splicing, can not only guarantee a smaller loss of pre-stress, but also improve the overall stiffness of the bridge.Therefore, it can be regarded as an optimized solution for fully prefabricated steel truss-concrete construction. The research results provide technical guidance for the assembly and construction of fully prefabricated composite steel-concrete continuous rigid frame bridges.更多还原