Effect of tensile modulus of GFRP on shrinkage and temperature reinforcement requirements in liquid containing structures

纤维增强聚合物(FRP)是由嵌入在聚合物树脂中的纤维制成的复合材料。它们被引入作为钢筋的替代方案。由于FRP筋的无磁性和无腐蚀性，可以防止电磁界面和钢筋的腐蚀。在过去的十年里，纤维增强聚合物(FRP)作为混凝土结构的加固复合钢筋得到了广泛的使用。除了耐腐蚀外，使用这种钢筋特别是玻璃纤维增强塑料(GFRPS)与传统钢筋相比还有许多优点，因为它具有更好的性能和成本效益等。对于暴露在腐蚀性环境条件下的结构物，包括含液体结构物(CLCS)和海洋结构物，混凝土的碱度会因暴露于盐、湿度、温度和导致钢筋腐蚀的氯化物而降低。这一过程 腐蚀会导致混凝土劣化，失去使用性能。为了防止腐蚀和变质，工程师们后来开始使用环氧涂层钢筋和玻璃钢。用GFRP代替钢筋加固CLCS是一个相当新的课题。加拿大和美国的FRP加固结构设计标准(CSA S806-12和ACI 440.1R-06)都简要提到了控制温度和收缩钢筋的最小配筋。这里建议进行一项全面的研究来解决这一问题。本研究旨在研究影响温度和收缩配筋的参数，特别是不同类型的GFRPS对拉伸模数的影响。还建议为用GFRP筋加固的结构提供指南，以将裂缝宽度限制在 可接受的水平。

Fiber reinforced polymers (FRP) are composite materials made of fibers embedded in a polymeric resin. They were introduced as an alternative replacement for steel reinforcement. Electromagnetic interface and steel corrosion could be prevented by FRP reinforcement due to their nonmagnetic and non-corrosive nature. There has been a widespread use of fiber reinforced polymers (FRPs) as reinforcing composite bars for concrete structures over the past decade. Other than being corrosion resistant, there are many advantages of using such reinforcing bars especially glass FRPs (GFRPs) over the conventional reinforcement due to enhanced properties, cost-effectiveness, among many others. For structures exposed to aggressive environmental situations including liquid containing structures (CLCS) and marine structures, the alkalinity of concrete is reduced by its exposure to salts, moisture, temperature and chlorides leading to steel corrosion. The process of corrosion will lead to concrete deterioration and lack of serviceability. In order to prevent corrosion and deterioration, engineers started using epoxy-coated bars and GFRPs later on. Using GFRP as a replacement for steel reinforcement for CLCS is a fairly new topic. Both Canadian and American standards for design of FRP reinforced structures (CSA S806-12 and ACI 440.1R-06) briefly mention on the minimum reinforcement for controlling temperature and shrinkage reinforcement. A comprehensive study is proposed here to address this issue. This study is aimed to investigate the parameters that influence the temperature and shrinkage reinforcement and in particular the effect of different types of GFRPs in terms of tensile modulus. It is also proposed to provide guidelines for structures reinforced with GFRP bars to limit the crack width to an acceptable level.