Durability study on reinforced concrete axial members retrofitted with fibre-reinforced cementitious matrix (FRCM)**********

纤维增强水泥基体（FRCM）加固钢筋混凝土轴杆的耐久性研究************

• 批准号: 537318-2018
• 负责人: ELREFAI, AHMED
• 金额: $ 1.82万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Engage Grants Program
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=650000
• 关键词: Durability; study; reinforced; concrete; axial

Fabric-reinforced cementitious matrix (FRCM) is a retrofitting system that has been introduced recently to retrofit/strengthen reinforced concrete (RC) structures. FRCM consists of one or more layers of anti-corrosive textiles made of carbon, glass, or Polyparaphenylene benzobisoxazole (PBO) grids that are sandwiched between layers of cementitious mortars. Unlike the epoxy-based fiber-reinforced polymers, mortars used in FRCM systems inherit the compatibility between the system and the concrete substrate since both materials have the cement as a common "base". To date, no data is available on the aging performance of FRCM-wrapped RC elements under the combined effect of axial loading and the exposure to harsh environmental conditions. The proposed research aims at examining such performance through a series of laboratory tests that will be conducted on RC prisms and cylinders wrapped with FRCM and tested under axial loads. The test parameters include the specimen's cross section (square and circular), the type of FRCM systems (2 types), the number of FRCM layers (1 or 2 layers), the specimen's condition prior to wrapping (conditioned or unconditioned), and the exposure condition after wrapping, which include (1) freeze-and-thaw cycles, (2) high temperatures, (3) humidity and high temperatures, (4) alkali solution, and (5) saltwater. Unconditioned specimens will be tested for reference. Specimens will be instrumented with strain gauges and/or compressometers to monitor the loads and strains during the test until failure occurs. Experimental results in terms of capacity, debonding, straining, modulus, and ductility will be recorded. The effect of different exposures on such quantities will be determined and verified against the provisions of ACI-549.4R-13. The results would be used to develop conceptual design rules for FRCM systems, which consider the effect of environmental aging in RC compression members such as columns and walls.

纤维增强胶凝基质（FRCM）是最近引入的一种加固系统，用于加固钢筋混凝土（RC）结构。FRCM由一层或多层由碳、玻璃或聚对苯二苯并异恶唑（PBO）网格制成的防腐纺织品组成，这些网格夹在胶凝砂浆层之间。与环氧基纤维增强聚合物不同，用于FRCM系统的砂浆继承了系统与混凝土基板之间的相容性，因为这两种材料都有水泥作为共同的“基础”。在轴向载荷和恶劣环境条件共同作用下，frp包覆RC构件的老化性能尚无相关数据。拟议的研究旨在通过一系列实验室测试来检验这种性能，这些测试将在钢筋混凝土棱柱和圆柱体上进行，并在轴向载荷下进行测试。试验参数包括试件截面（方形和圆形）、FRCM体系类型（2种）、FRCM层数（1层或2层）、包裹前试件状态（有条件或无条件）、包裹后暴露状态，包括(1)冻融循环、(2)高温、(3)湿热高温、(4)碱溶液、(5)盐水。非条件试样将进行测试以供参考。试样将用应变计和/或压缩计来监测试验期间的载荷和应变，直到发生故障。将记录容量、脱粘、应变、模量和延性方面的实验结果。将根据ACI-549.4R-13的规定确定和验证不同暴露对这些数量的影响。研究结果将用于制定FRCM体系的概念设计规则，该规则将考虑环境老化对RC受压构件（如柱和墙）的影响。