【作者】 余自若； 阎贵平； 唐国栋； 程俊瑞；

【Author】 YU Ziruo ,YAN Guiping, TANG Guodong,CHENG Junrui(School of Civil Engineering & Architecture,Beijing Jiaotong University,Beijing 100044,China)

【机构】 北京交通大学；

【摘要】 本文介绍了最近在北京交通大学开展的铁路RPC箱梁抗弯承载能力的试验研究。RPC(活性粉末混凝土)是一种新型的高性能混凝土,具有许多优越的性能,但目前国内对其实际工程应用的研究尚且开展得很少。本试验对用RPC设计的24m铁路箱梁在工作荷载下的承载力进行了研究。在模型梁上进行了四点加载,观测了梁在运营荷载下的受力变形、抗裂性能,并进行了正截面受弯分析。结果表明:(1)该箱梁能满足铁路承载能力需要;(2)若梁采用RPC制成,可以大大减小截面面积,有利于降低结构自重,便于预制、运输和装配;另外,利用RPC的高抗剪性能,可以减少甚至取消结构中的箍筋和辅助配筋,降低钢筋用量;(3)分析结果表明该RPC箱梁可以用于铁路桥梁,拟用于青藏铁路桥梁的实际工程中。更多还原

【Abstract】 This paper focuses on recent research conducted at the Beijing Jiaotong University on applications of reactive powder concrete (RPC) to railway box girder bridges. As a new high-performance concrete,RPC exhibits many excellent performances,but the application of this new material is still limited in our country. So an experiment study has been carried out to evaluate the behaviors of RPC railway box girders bridges with 24m span under working load. In this study, a small-scale model has been constructed to investigate flexural performance, crack resistance and displacement of girders cast with RPC under four-point flexural loading. The check of working stage,and the analysis of the relationship between load and deflection are presented. Experimental results indicate that (1) the box girder satisfies the requirement of carrying capacity of the railway bridge;(2) If reinforced concrete box girder bridges are made of RPC rather than normal concrete, the section size of the girder will be decreased, the gravity and the quantities will be reduced largely. So the girder will be easy to pre-cast,transport and assemble. On the other hand.RPC can share the shear in the girder,this characteristic ensures that auxiliary reinforcements can be cancelled in this kind pre-cast pre-stressed box girder bridges so that the consumptions of reinforcing steel will be reduced; (3) The analysis shows that this RPC box girder bridge can be applied to railway bridges,as a result,in the foreseeable future it would soon be applied to Qingzang railway bridges.更多还原