Abstract The large number of existing masonry bridges still in service in the world roadway and railway networks requires that transportation system managers carry out ordinary and extraordinary maintenance. In many of these networks, the need for increasing the speed and/or weight of the traffic loads also entails the design of strengthening interventions aimed at enhancing the load-carrying capacity of masonry bridges. Among the available techniques for the strengthening of these structures, the use of fiber reinforced cementitious matrix (FRCM) composites has gained popularity due to their advantages with respect to more traditional techniques. More recently, the use of steel fiber reinforced mortars (SFRM), has also been investigated for the strengthening of masonry bridges, with promising results. In this paper, a limit analysis for assessing the vertical load-carrying capacity of single-span bridges strengthened with FRCM or SFRM, applied at the intrados, is described, and calibrated using available experimental results. The document highlights the variables that should be considered in such procedure and also discusses the similarities and differences between the two strengthening techniques. A subsequent parametrical analysis shows that both techniques produce comparable increments in the load carrying capacity of the masonry bridges when compared to unstrengthened conditions. In addition, it was seen that if the finite friction between blocks is not considered when performing the limit analysis of masonry bridges, the ultimate load capacity of the arches can be overestimated as the failure mode can be attained due to shear sliding of the masonry blocks, a hinge mechanism or a combination of both.

中文翻译：

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用极限分析法评估用 FRCM 或 SFRM 加固的砌体拱桥的竖向承载能力

摘要 世界公路和铁路网络中仍在使用的大量现有砌体桥梁要求运输系统管理人员进行日常和非日常维护。在许多这样的网络中，为了提高交通负载的速度和/或重量，还需要设计加强干预措施，旨在提高砖石桥梁的承载能力。在用于加固这些结构的可用技术中，纤维增强水泥基 (FRCM) 复合材料的使用因其相对于更传统技术的优势而广受欢迎。最近，还研究了使用钢纤维增强砂浆 (SFRM) 来加固砌体桥梁，并取得了可喜的成果。在本文中，描述了用于评估用 FRCM 或 SFRM 加固的单跨桥梁的垂直承载能力的极限分析，应用在内部结构上，并使用可用的实验结果进行校准。该文件重点介绍了此类程序中应考虑的变量，并讨论了两种强化技术之间的异同。随后的参数分析表明，与未加固的条件相比，这两种技术在砌体桥梁的承载能力方面产生了可比的增量。此外，如果在进行砌体桥梁的极限分析时不考虑砌块之间的有限摩擦，则