摘   要：国内高速铁路32 m简支箱梁均采用整孔运输、架设施工，简支梁向更大跨度发展需解决梁重增加这一主要矛盾。超高性能混凝土（UHPC）材料是一种新型纤维增强水泥基复合材料，用其建造桥梁可以减小结构尺寸。为实现铁路大跨度简支梁整孔运架技术，对24 m UHPC简支箱梁的主要构造进行了设计计算，并结合24 m UHPC试验梁的制作提出了主要施工工艺要求。结果表明，高速铁路UHPC简支箱梁理论计算可行，可推广至更大跨度简支梁的建造实践；结合结构受力要求宜选用水胶比较高的UHPC材料；UHPC箱梁的模板应设计为内模可伸缩体系以适应材料收缩变形较大的特点。UHPC节段蒸养应严格按照升温、恒温、降温三个阶段蒸养。
Abstract: 32 m simply supported beam integrally prefabricated and erected for High-Speed railway is very popular. The main contradiction of increasing beam weight should be solved in the development of simply supported beams to larger span. Ultra-high Performance Concrete(UHPC) is a new fiber enhancement cement-based composite materials. The size of the structure can be more slender by using UHPC. In order to realize the whole-hole transportation and erection technology of railway long-span simple-supported beam, the main structure of 24 m UHPC simple-supported box girder is designed and calculated. Combined with the manufacture of 24 m UHPC test beam, the main construction technology requirements are put forward. The results show that the theoretical calculation of UHPC simple-supported box girder for high-speed railway is feasible and can be extended to the construction practice of large-span simple-supported girder; UHPC material with high water-cement ratio should be selected in combination with structural stress requirements; the formwork of UHPC box girder should be designed as an internal modular retractable system to adapt to the characteristics of material shrinkage and deformation. Steaming of UHPC segments should be strictly carried out in three stages: heating, constant temperature and cooling.