基于耐久性的节段预制拼装箱梁桥优化设计

Optimization Design of Segmental Prefabricated Assembled Box Girder Bridge Based on Durability

为进一步优化节段预制拼装箱梁桥的设计,以某节段预制拼装连续刚构箱梁桥为研究对象,借助数值模拟技术,从预制阶段结构的水化热变形这一重要角度,探讨了不同宽长比和配合比节段预制拼装箱梁桥的耐久性,研究得出结论:建议控制宽长比(W/L)保持在小于10的范围内;建议在混凝土配合比设计过程中掺加粉煤灰等添加剂,若条件允许,可采用粉煤灰+矿粉双掺配合比。研究结果可为节段预制拼装箱梁桥的优化设计提供理论依据和实践指导。

In order to further optimize the design of segmental prefabricated assembled box girder bridges,a continuous rigid frame box girder bridge with segmental prefabricated assembly was taken as the research object.With the help of numerical simulation technology,the durability of segmental prefabricated assembled box girder bridges with different width to length ratios and mix proportions was explored from the important perspective of hydration heat deformation during the prefabrication stage.The conclusion was drawn that it is recommended to control the width to length ratio(W/L)within the range of less than 10;It is recommended to add additives such as fly ash in the concrete mix design process.If conditions permit,a dual mix ratio of fly ash and mineral powder can be used.The obtained results can provide theoretical basis and practical guidance for the optimization design of segmental prefabricated assembled box girder bridges.