Serviceability and strength of FRP reinforced concrete structures

加拿大面临的主要挑战之一是有效地维护和扩大我们广泛的桥梁、公路和其他关键基础设施网络，这些网络对加拿大人的生活质量以及国家的经济竞争力和未来发展至关重要。为了应对这一挑战，我们需要建设新的基础设施，维护和修复现有基础设施。其中很大一部分是由钢筋混凝土制成的，混凝土桥梁、停车场、电线杆等由于除冰盐引起的钢筋腐蚀而迅速恶化。这个问题可以通过用纤维增强聚合物（FRP）代替钢筋来解决。FRP耐腐蚀、耐用，可用于现有结构的改造和新钢筋混凝土结构的加固。然而，安全，有效和经济地使用FRP需要以严格的科学原理为基础的方法和技术，并通过适当的实验进行验证。此外，为了确保研究结果在实践中得到应用，需要简化严格的方法，以纳入设计规范。建议的研究是为了实现上述目标的一些重要问题，在设计和改造的混凝土结构，涉及FRP。为了确保FRP加固混凝土结构的安全性，将研究其在剪切、扭转和弯矩引起的复合应力场下的性能和强度，并提出设计建议。为了防止FRP加固板-角柱连接在剪力和不平衡弯矩共同作用下发生意外冲剪破坏，本研究将首次探讨这一问题。 在拟议的研究中，新的锚固和改造系统进行了调查，以防止过早分层，特别关注分层的情况下，混凝土构件改造的剪切强度增加。研究结果将用于制定相对简单的程序，供结构设计师应用，并纳入设计标准。

One of the major challenges in Canada is to effectively maintain and expand our extensive networks of bridges, highways and other key elements of infrastructure that are essential to the quality of life of Canadians and to the economic competitiveness and future development of the country. To meet this challenge, we need to build new infrastructure and maintain and repair existing ones. A significant portion of these is made of reinforced concrete, and concrete bridges, parking structures, utility poles, etc. are rapidly deteriorating due to corrosion of steel reinforcement caused by deicing salts. This problem can be solved by replacing steel reinforcement by fibre reinforced polymers (FRP). FRP are corrosion resistant and durable and can be used for the retrofit of existing structures and reinforcement of new reinforced and prestressed concrete structures. However, safe, effective and economic use of FRP needs methods and techniques that are underpinned by rigorous scientific principles, validated by appropriate experiments. Furthermore, to ensure that the results of research are applied in practice, the rigorous methods need be simplified for inclusion in design codes. The proposed research is aimed at fulfilling the above objectives with respect to a number of important problems in the design and retrofit of concrete structures involving FRP. To ensure the safety of FRP reinforced concrete structures, their behaviour and strength under combined stress fields caused by shear, torsion and moment will be investigated and design recommendations will be made. To prevent unexpected punching shear failure in FRP reinforced slab- corner column connections under combined shear and unbalanced moment, this problem will be investigated for the first time in the proposed research. In the proposed study novel anchoring and retrofit systems are investigated to prevent premature delamination, with particular focus on delamination in cases of concrete members retrofitted for increased shear strength. The research results will be used to formulate relatively simple procedures for application by structural designers and for inclusion in design standards.