scholarly journals The effect of temperature on the mechanical properties of hybrid FRP bars applicable for the reinforcing of concrete structures

2020 ◽  
Vol 322 ◽  
pp. 01029
Author(s):  
Karolina Ogrodowska ◽  
Karolina Łuszcz ◽  
Andrzej Garbacz
Keyword(s):  
Mechanical Properties ◽  
Carbon Fibers ◽  
Concrete Structures ◽  
Fiber Reinforced Polymer ◽  
Effect Of Temperature ◽  
Fiber Reinforced ◽  
Reinforcing Bars ◽  
Frp Composites ◽  
Reinforced Polymer ◽  
Frp Bars

One of the most common causes of the deterioration of concrete structures is the corrosion of steel reinforcement. Reinforcement made from fiber reinforced polymers (FRP) is considered to be an attractive substitution for traditional reinforcement. The most popular FRP reinforcing bars are made of glass fibers. Basalt fiber reinforced polymer (BFRP) is a relatively new material for reinforcing bars. The main drawback of BFRP bars is their low modulus of elasticity. A new type of bar made from hybrid fiber reinforced polymer (HFRP) in which a proportion of the basalt fibers are replaced with carbon fibers can be considered as a solution to this issue; such a bar is presented in this work. The HFRP bars might be treated as a relatively simple modification to previously produced BFRP bars. A different technical characteristic of the fibre reinforced polymer makes the designing of structures with FRP reinforcement differ from conventional reinforced concrete design. Therefore, it is necessary to identify the differences and limitations of their use in concrete structures, taking into account their material and geometric features. Despite the predominance of FRP composites in such aspects as corrosion resistance, high tensile strength, and significant weight reductions of structures – it is necessary to consider the behavior of FRP composites at elevated temperatures. In this paper, the effect of temperature on the mechanical properties of FRP bars was investigated. Three types of FRP bar were tested: BFRP, HFRP in which 25% of basalt fibers were replaced with carbon fibers and nHFRP in which epoxy resin was additionally modified with a nanosilica admixture. The mechanical properties were determined using ASTM standard testing for transverse shear strength. The tests were performed at -20°C, +20°C, +80°C for three diameters of each types of bar.

Study of Crack Width of the Fiber Reinforced Polymer Beam

2011 ◽  
Vol 243-249 ◽  
pp. 806-811 ◽  
Author(s):  
Qin Xu ◽  
Wei Huang ◽  
Hao Zhen Wu ◽  
Jun Yuan Wang ◽  
Jie Yu Liu
Keyword(s):  
Mechanical Properties ◽  
Reinforced Concrete ◽  
Structural Engineering ◽  
Concrete Structures ◽  
Analytical Formula ◽  
Reinforced Concrete Beam ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Reinforced Polymer ◽  
Frp Bars

Fiber reinforced polymer (FRP) is a new kind of material for structural engineering in recent year. The partial inferiority of the bond and mechanical properties for FRP bars, however, leads to wider cracks compared with those of steel-reinforced concrete structures. Therefore, current design methods for predicting crack widths developed in concrete structures reinforced with steel bars at service load may not be used for concrete structures reinforced with FRP bars. This paper presents an analytical formula that calculates the maximum crack with in FRP- reinforced concrete beam, taking into account both the bond and the mechanical properties of FRP bars. The experimental results compared well with those proposed by the model.

scholarly journals Durability of Externally Bonded Fiber-Reinforced Polymer Composites in Concrete Structures: A Critical Review

Polymers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 765
Author(s):  
Jovan Tatar ◽  
Sandra Milev
Keyword(s):  
Polymer Composites ◽  
Critical Review ◽  
Concrete Structures ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Frp Composites ◽  
Reinforced Polymer ◽  
Fiber Reinforced Polymer Composites ◽  
Interdisciplinary Approaches ◽  
Externally Bonded

Externally bonded fiber-reinforced polymer composites have been in use in civil infrastructure for decades, but their long-term performance is still difficult to predict due to many knowledge gaps in the understanding of degradation mechanisms. This paper summarizes critical durability issues associated with the application of fiber-reinforced polymer (FRP) composites for rehabilitation of concrete structures. A variety of factors that affect the longevity of FRP composites are discussed: installation, quality control, material selection, and environmental conditions. Critical review of design approaches currently used in various international design guidelines is presented to identify potential opportunities for refinement of design guidance with respect to durability. Interdisciplinary approaches that combine materials science and structural engineering are recognized as having potential to develop composites with improved durability.

Effect of post-curing heat treatment on mechanical properties of fiber reinforced polymer (FRP) composites

2017 ◽  
Vol 59 (4) ◽  
pp. 366-372 ◽  
Author(s):  
Cagri Uzay ◽  
Mete Han Boztepe ◽  
Melih Bayramoğlu ◽  
Necdet Geren
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Frp Composites ◽  
Reinforced Polymer

Anchorage systems for reinforced concrete structures strengthened with fiber-reinforced polymer composites: State-of-the-art review

2020 ◽  
Vol 39 (9-10) ◽  
pp. 327-344
Author(s):  
Qiang Wang ◽  
Hong Zhu ◽  
Bai Zhang ◽  
Yixuan Tong ◽  
Fei Teng ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
State Of The Art ◽  
Concrete Structures ◽  
Fiber Reinforced Polymer ◽  
Reinforced Concrete Structures ◽  
Fiber Reinforced ◽  
Advantages And Disadvantages ◽  
Frp Composites ◽  
Reinforced Polymer ◽  
Anchorage System

Fiber-reinforced polymer (FRP) composites have been widely used to strengthen the deteriorated reinforced concrete structures due to their outstanding characteristics of light weight, high strength, as well as noncorrosion. A successful strengthening with the FRP composites would equip the existing structures with the prominent improvement in terms of the durability, ductility, and bearing capacity. Current studies indicate that a simple and reliable anchorage system for the FRP composites will help improve the performance of the strengthened structures both efficiently and economically. Up till now, various anchorage systems have been developed for the FRP composites. Therefore, it is necessary to select appropriate anchorage systems according to different needs and establish relevant design specifications. In view of the aforementioned objectives, this paper systematically summarizes the anchoring mechanism of anchorage systems for two commonly used FRP products (FRP laminates and FRP bars) in different strengthened systems. Additionally, a state-of-the-art review as well as the advantages and disadvantages of each anchorage system are presented. Finally, shortcomings in the current state of knowledge and recommendations beneficial to further study are put forward.

scholarly journals Application of basalt-FRP bars for reinforcing geotechnical concrete structures

2019 ◽  
Vol 265 ◽  
pp. 05011
Author(s):  
Marta Kosior-Kazberuk
Keyword(s):  
Mechanical Properties ◽  
Limit State ◽  
Basalt Fiber ◽  
Fiber Reinforced Polymer ◽  
Ultimate Limit State ◽  
Fiber Reinforced ◽  
Reinforced Polymer ◽  
Metallic Reinforcement ◽  
Frp Bars ◽  
Basalt Fiber Reinforced Polymer

The fiber reinforced polymer (FRP) bars have become a useful substitute for conventional reinforcement in civil engineering structures for which load capacity and resistance to environmental influences are required. They are often used in concrete structural elements exposed to strong environmental aggression, such as foundations, breakwaters and other seaside structures, road structures and tanks. The basalt fiber-reinforced polymer (BFRP) is the most recently FRP composite, appearing within the last decade. Due to their mechanical properties different from steel bars, such as higher tensile strength and lower Young's modulus, BFRP bars are predestined for use in structures for which the ultimate limit state is rather decisive than serviceability limit state. Experimental tests were carried out to assess the influence of static long-term loads and cyclic freezing/thawing on the behaviour of concrete model beams with non-metallic reinforcement. The bars made of basalt fiber reinforced polymer (BFRP) and hybrid (basalt and carbon) fiber reinforced polymer (HFRP) were used as non-metallic reinforcement. The mechanical properties of both types of bars were also determined.

scholarly journals Strength Degradation in Curved Fiber-reinforced Polymer (FRP) Bars Used as Concrete Reinforcement

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1653
Author(s):  
Thanongsak Imjai ◽  
Reyes Garcia ◽  
Maurizio Guadagnini ◽  
Kypros Pilakoutas
Keyword(s):  
Tensile Strength ◽  
Structural Damage ◽  
Mechanical Performance ◽  
Failure Criteria ◽  
Strength Degradation ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Frp Composites ◽  
Reinforced Polymer ◽  
Frp Bars

Steel reinforcements in concrete tend to corrode and this process can lead to structural damage. Fiber-reinforced polymer (FRP) reinforcements represent a viable alternative for structures exposed to aggressive environments and have many possible applications where superior corrosion resistance properties are required. The use of FRP rebars as internal reinforcements for concrete, however, is limited to specific structural elements and does not yet extend to the whole structure. The reason for this relates to the limited availability of curved or shaped reinforcing FRP elements on the market, as well as their reduced structural performance. This article presents a state-of-the art review on the strength degradation of curved FRP composites, and also assesses the performance of existing predictive models for the bend capacity of FRP reinforcements. Previous research has shown that the mechanical performance of bent portions of FRP bars significantly reduces under a multiaxial combination of stresses. Indeed, the tensile strength of bent FRP bars can be as low as 25% of the maximum tensile strength developed in a straight counterpart. In a significant number of cases, the current design recommendations for concrete structures reinforced with FRP were found to overestimate the bend capacity of FRP bars. A more accurate and practical predictive model based on the Tsai–Hill failure criteria is also discussed. This review article also identifies potential challenges and future directions of research for exploring the use of curved/shaped FRP composites in civil engineering applications.

BFRP Bars as an Alternative Reinforcement of Concrete Structures - Compatibility and Adhesion Issues

2015 ◽  
Vol 1129 ◽  
pp. 233-241 ◽  
Author(s):  
Andrzej Garbacz ◽  
Marek Urbański ◽  
Andrzej Łapko
Keyword(s):  
Concrete Structures ◽  
Basalt Fiber ◽  
Technical Characteristic ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced Polymers ◽  
Fiber Reinforced ◽  
Reinforcing Bars ◽  
Reinforced Polymers ◽  
Reinforced Polymer ◽  
Reinforced Beams

One of the most common causes of damage to concrete structures is the corrosion of the reinforcement. Reinforcement made from Fiber Reinforced Polymers (FRP) is considered as an attractive substitution of traditional steel reinforcement. A different technical characteristic of fiber reinforced polymer makes designing structures with FRP reinforcement differs from conventional reinforced concrete design. Therefore, it is necessary to identify the differences and limitations of their use in the concrete structures, taking into account their material and geometrical features. Basalt Fiber Reinforced Polymer (BFRP) is a relatively new material for reinforcing bars. On the basis of the ACI 440.1R-06 guidelines as well as experimental results for selected BFRP reinforced beams a model of compatibility in a system: BFRP bar - concrete was proposed. Additionally, based on the results of FEM simulations, the effect of BFRP bars ribbing on their adhesion to concrete was discussed.

Sign in / Sign up

Export Citation Format

Share Document