Experimental Study on Axial Compression of FRP Confined Concrete Column

2012 ◽  
Vol 461 ◽  
pp. 682-685
Author(s):  
Yang Yang Han ◽  
Hao Zhang ◽  
Ya Qin Li ◽  
Jia Yao ◽  
Xiao Ping Hu
Keyword(s):  
Cross Section ◽  
Concrete Columns ◽  
Fiber Reinforced Polymer ◽  
Confined Concrete ◽  
Carbon Fiber Reinforced Polymer ◽  
Strengthening Effect ◽  
Fiber Reinforced ◽  
Concrete Members ◽  
Construction Methods ◽  
Reinforced Polymer

Abstract: Concrete members strengthened by fiber reinforced polymer (FRP) are increasingly becoming a popular retrofit technique in recent years due to the excellent material properties, convenient and easy construction methods, and outstanding strengthening effect. However, fundamental researches are incomplete; especially the characteristics research of square cross-section of FRP confined concrete has become a major obstacle for the development of further research and application. Therefore, the better understanding of the behavior of confined concrete becomes of paramount importance. A total of 10 concrete columns, which were reinforced with CFRP (carbon fiber reinforced polymer) and with filleted square sections, were fabricated and tested subjected to axial load to investigate the mechanical properties of FRP confined concrete. The mechanical behavior of FRP confined concrete has been further understood and some useful conclusions are obtained.

scholarly journals Ductility Evaluation of Damaged Recycled Aggregate Concrete Columns Repaired With Carbon Fiber-Reinforced Polymer and Large Rupture Strain FRP

2020 ◽  
Vol 7 ◽  
Author(s):  
Pengda Li ◽  
Yao Zhao ◽  
Xu Long ◽  
Yingwu Zhou ◽  
Zhenyuan Chen
Keyword(s):  
Concrete Columns ◽  
Recycled Aggregate Concrete ◽  
Fiber Reinforced Polymer ◽  
Confined Concrete ◽  
Recycled Aggregate ◽  
Carbon Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Aggregate Concrete ◽  
Reinforced Polymer ◽  
Concrete Cylinders

The inherent defects of recycled aggregate concrete (RAC) include the complex interfacial transition zone (ITZ) and the many micro-cracks that appear during its producing process, which result in some inferior mechanical properties compared with natural aggregate concrete (NAC). This drawback usually prevents RAC from being selected for structural purposes. Existing research has shown that the strength and ductility of damaged concrete in compression members can be significantly enhanced through external confinement using fiber-reinforced polymer (FRP) wraps. This application has been widely used in concrete structural repair and retrofitting technology. However, research on the effects of RAC damage coupled with different load damage conditions is rare, as is information on the mechanical properties of RAC reinforced with FRP jackets. This paper presents the results of an experimental study on the behavior of pre-damaged recycled aggregate concrete cylinders that were repaired with carbon fiber-reinforced polymer (CFRP) or large rupture strain (LRS)-FRP jackets. Tests were conducted on 58 concrete cylinders with variations in the replacement ratio, damage levels, and FRP properties. Test results demonstrated that the ultimate strain and strength of damaged recycled aggregate concrete could be significantly enhanced by FRP jackets and that aggregate quality plays a vital role in the strength of confined concrete. Also, the energy absorption of CFRP- and LRS-FRP-confined RAC were evaluated. The analysis indicated that, compared with CFRP-confined RAC, LRS-FRP can greatly improve the energy absorption capacity of RAC; thus, LRS-FRP confined concrete has a good potential to achieve a ductile design for concrete columns, especially when used in seismic reinforcement.

Behavior and modeling of post-heated circular concrete specimens repaired with fiber-reinforced polymer composites

2021 ◽  
pp. 136943322110585
Author(s):  
Seyed Mehrdad Elhamnike ◽  
Rasoul Abbaszadeh ◽  
Vahid Razavinasab ◽  
Hadi Ziaadiny
Keyword(s):  
Strain Curve ◽  
Concrete Columns ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Stress Strain Curve ◽  
Stress Strain ◽  
Concrete Members ◽  
Frp Composites ◽  
Reinforced Polymer ◽  
Fiber Reinforced Polymer Composites

Exposure of buildings to fire is one of the unexpected events during the life of the structure. The heat from the fire can reduce the strength of structural members, and these damaged members need to be strengthened. Repair and strengthening of concrete members by fiber-reinforced polymer (FRP) composites has been one of the most popular methods in recent years and can be used in fire-damaged concrete members. In this paper, in order to provide further data and information about the behavior of post-heated circular concrete columns confined with FRP composites, 30 cylindrical concrete specimens were prepared and subjected under four exposure temperatures of 300, 500, 700, and 900. Then, specimens were repaired by carbon fiber reinforced polymer composites and tested under axial compression. Results indicate that heating causes the color change, cracks, and weight loss of concrete. Also, with the increase of heating temperature, the shape of stress–strain curve of FRP-retrofitted specimens will change. Therefore, the main parts of the stress–strain curve such as ultimate stress and strain and the elastic modulus will change. Thus, a new stress–strain model is proposed for post-heated circular concrete columns confined by FRP composites. Results indicate that the proposed model is in a good agreement with the experimental data.

Investigation of the behavior of circular concrete columns reinforced with carbon fiber reinforced polymer (CFRP) jackets

1999 ◽  
Vol 26 (5) ◽  
pp. 590-596 ◽  
Author(s):  
Burt K Purba ◽  
Aftab A Mufti
Keyword(s):  
Reinforced Concrete ◽  
Carbon Fiber ◽  
Concrete Columns ◽  
Fiber Reinforced Polymer ◽  
Fiber Reinforced Polymers ◽  
Carbon Fiber Reinforced Polymer ◽  
Fiber Reinforced ◽  
Reinforced Concrete Columns ◽  
Reinforced Polymer ◽  
Carbon Fiber Reinforced

Recent advancements in the fields of fiber reinforced polymers (FRPs) have resulted in the development of new materials with great potential for applications in civil engineering structures, and due to extensive research over recent years, FRPs are now being considered for the design of new structures. This study describes how carbon fiber reinforced polymer jackets can be used to reinforce circular concrete columns. Fibers aligned in the circumferential direction provide axial and shear strength to the concrete, while fibers aligned in the longitudinal direction provide flexural reinforcement. Prefabricated FRP jackets or tubes would also provide the formwork for the columns, resulting in a decrease in labor and materials required for construction. Also, the enhanced behavior of FRP jacketed concrete columns could allow the use of smaller sections than would be required for conventionally reinforced concrete columns. Furthermore, FRP jacket reinforced concrete columns would be more durable than conventionally reinforced concrete columns and therefore would require less maintenance and have longer service life.Key words: bridge, carbon, column, concrete, confinement, fiber reinforced polymer, jacket, retrofitting, seismic, strengthening.

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