超高性能混凝土在桥梁工程中的应用

超高性能混凝土(UHPC)是一种新型高性能水泥基复合材料,具有超高的耐久性和力学性能。UH-PC在桥梁工程中的应用,可优化桥梁结构尺寸、增大跨径,在增加承载力、耐久性和寿命周期的同时保持较小的变形。但由于原材料质量和配比的差异及大型搅拌设备不成熟等因素,连续制备性能较好的UHPC难度较大,同时相关桥梁设计规范较不完善和实践指导设计的经验较少,另外严格的养护制度制约了桥梁施工方法的灵活选择,导致目前UHPC不能在桥梁中广泛应用。为了促进UHPC大规模应用,简要介绍加拿大和美国2座UHPC桥梁应用情况。随着UHPC制备技术的进步、设计理论的完善,其必将在桥梁中得到广泛应用。

Application of Ultra-High Performance Concrete in Bridge Engineering

Ultra-high performance concrete(UHPC) is an emerging cement-based composite material which exhibits excellent durability and mechanical behavior.In bridge engineering,the application of UHPC ensures the optimization of structural dimension and the increase of span and also makes the structure maintain little deformation while the bearing capacity,durability and life circle are increased.It is difficult to continuously produce UHPC with high quality due to the variation of the quality and mixing proportion of raw materials and the immature large mixing equipment.Meanwhile,UHPC has not been widely used in bridge engineering currently because the relevant bridge design code is not perfect and the experience directing design is little;in addition,the strict maintenance regulation restricts the flexible select of bridge construction methods.To promote the large scale application of UHPC,the application of UHPC on two bridges in Canada and America is introduced.With the development of preparing technique of UHPC and the perfection of design theory,UHPC will certainly get wide application in bridge engineering.