大悬臂预应力组合桥面板实用计算方法

Applied Computational Method of Long Cantilevered Prestressed Composite Bridge Deck

为了解决不同位置荷载作用下组合桥面板的荷载横向分布计算问题,根据脊骨梁中波形钢腹板挑梁并排支撑的预应力大悬臂组合桥面板的受力特点及抗弯和抗扭刚度沿挑梁纵向的变化规律,采用基于换算截面法的修正刚接梁法,假设受载挑梁的荷载横向分布系数随荷载作用位置变化沿挑梁纵向按三次曲线分布。然后,根据"波形钢腹板不抵抗弯矩"的结论和拟平截面假定,推导出波形钢腹板组合挑梁的开裂弯矩和弹性极限弯矩计算公式。最后,通过试验和有限元分析来验证该公式的正确性。结果表明:该计算公式能够满足工程设计的精度要求。

In order to calculate the load transverse distribution of composite bridge deck at different load positions, according to the mechanical characteristics of the prestressed composite bridge deck beam supported by side-by-side long cantilever beams with corrugated steel webs on spine girder and variation rules of bending resistant and anti-torsional rigidity along vertical cantilever beam, authors proposed the modified rigid-connected beam method based on transformed section method. The method supposed that the load lateral distribution factor of the loading cantilever beam along the longitudinal axis varied in terms of the cubic curves. Then, the formulas for cracking bending moment and elastic ultimate moment of the composite cantilever beam with corrugated webs were proposed based on the quasi plane assumption and the common conclusion that the corrugated steel webs did not resist bending moment. Finally, the effectiveness and accuracy of the formulas for pract comparing those with the results of experiment and fin cal engineering design were verified by te element analysis.