大跨连续组合箱梁桥面板轮载作用分析

Wheel Load of Bridge Deck of Large-Span Continuous Composite Box Girder

结合工程实例,介绍了大跨连续组合箱梁桥面板在汽车轮载作用下的空间有限元仿真分析方法,并将分析结果与相关文献的简化方法计算结果进行了对比。结果表明:简化方法结果较有限元结果整体偏高。对于桥面板块跨中弯矩,简支板模型偏高29%以上,连续板模型偏高15%以上;对于板块支点处弯矩,连续板模型由于没有考虑内力的重分布,计算结果偏高51%以上。初步设计阶段建议采用连续板模型估算轮载作用下桥面板板块跨中弯矩。

Combining with the engineering case study, a spatial simulation method based on FEM is introduced to analyze the wheel load of bridge deck in the large-span continuous bridge with composite boxgirder. The results of the analysis are compared with those got by the simplified methods in relative literature review. The comparison shows that the results got by simplified methods are higher than those got by FEM in general. For the moments in the middle span of bridge deck, the result of simply-supported plate model got by simplified method is over 29% higher than that got by FEM ;the result of continuous plate model got by simplified method is over 15% higher than that got by FEM. For the moments at the supporting point of the plate, the result is over 51% higher than the result got by FEM, for the simplified method takes no consideration of the re-distribution of internal forces. The continuous plate model is recommended to estimate the moments in the middle span of bridge deck ureter the wheel load at the first stage of design.