C55聚丙烯纤维高性能混凝土在铁路桥梁主体结构中应用技术研究

摘要

Polypropylene fiber reinforced concrete can effectively improve the concrete crack resistance, long-term work-ing performance and deformation capacity and durability, at present has been widely applied in military, traffic, housing construction, airport, water conservancy engineering, etc. in China, and mostly used in beam body pavement, etc. but not many in main structure of the bridge engineering. Combined with Tianjiayao No. 2 bridge project, full-scale theoreti-cal research and test on polypropylene fibre selection, mix design, mixing process, crack resistance, upper air pumping and hydration heat monitoring and analysis are performed to ensure the quality of C55 polypropylene fiber concrete ap-plied in railway bridge structure for the first time and form a set of mature and reliable construction technology.%聚丙烯纤维混凝土由于它能有效地提高混凝土抗裂性、改善长期工作性能、提高变形能力和耐久性，目前已经在国内的军事、交通、房建、机场、水利等工程上得到广泛的应用。桥梁工程中主要用于梁体铺装层等部位，在桥梁主体结构中使用聚丙烯纤维混凝土案例并不多见。文章结合田家窑2号大桥工程，从聚丙烯纤维的选择、配合比设计、拌合工艺、抗裂性能、高空泵送和水化热监控与分析进行了全面的理论研究和试验测试，确保了C55聚丙烯纤维混凝土在铁路桥梁结构中的首次运用质量，形成了一套成熟可靠的施工技术。