scholarly journals Numerical Analysis on Flexural Behavior of Steel Fiber-Reinforced LWAC Beams Reinforced with GFRP Bars

2019 ◽  
Vol 9 (23) ◽  
pp. 5128 ◽  
Author(s):  
Yijia Sun ◽  
Yang Liu ◽  
Tao Wu ◽  
Xi Liu ◽  
Haodan Lu

Three-dimensional nonlinear finite-element (FE) models using an explicit algorithm were established to simulate the behavior of beams reinforced with glass fiber-reinforced polymer (GFRP) bars cast using lightweight aggregate concrete (LWAC) with and without steel fibers, and the progressive damage model was employed to simulate the rupture of GFRP. The developed FE model was evaluated by test results, and it exhibited good agreement with the test results in terms of moment–deflection response, serviceability performance, ultimate capacity, and failure mode. Influencing factors, including the section height, reinforcement ratio, and span length were discussed according to the established FE model. It was revealed that the reinforcement ratio corresponding to balanced failure was higher than that given by code ACI 440.1R, which confirmed the necessity of the amplification factor of a balanced reinforcement ratio to ensure concrete crushing of the beam. For specimens that failed due to concrete crushing, the increase in fiber-reinforced polymer (FRP) reinforcement ratio did not significantly improve the ultimate capacity, but it did have an obvious effect on the reduction of deflection at service load. Moreover, a greater reinforcement ratio was needed for beams when the span length increased.

2020 ◽  
pp. 136943322097478
Author(s):  
Abu Sayed Mohammad Akid ◽  
Qudrati Al Wasiew ◽  
Md. Habibur Rahman Sobuz ◽  
Touhidur Rahman ◽  
Vivian WY Tam

Fiber-reinforced polymer (FRP) is a revolutionary breakthrough in the history of structural engineering innovation due to its unique characteristics to strengthen and repair the deficient reinforced concrete structures. This paper aimed at evaluating the flexural characteristics of jute fiber reinforced polymer (JFRP) bonded reinforced concrete beams. The influence of the test variables comprised of strengthening scheme and corrosion rate for reinforced concrete (RC) beams. The experimental study comprised of casting six RC beams and testing them in flexure loading. To determine the flexural response of RC beams, three beams were fabricated with JFRP laminate having a level of corrosion of 0%, 7.5%, and 15%, whereas three beams were designated as control beams having same corrosion levels with no JFRP. Test results indicated that all JFRP strengthened beams exhibited increased ultimate load, yield load, first cracking load, and lower ductility index compared to control beams. The results also revealed that JFRP strengthening technique improved the flexural strength of the corroded beams efficiently, albeit the ultimate load of the beams diminished with higher corrosion level. Analytical calculations were carried out for quantifying the flexural characteristics and mass loss of beams which provided a good agreement with the test results.


2014 ◽  
Vol 1079-1080 ◽  
pp. 258-265
Author(s):  
Chen Ning Cai ◽  
Shan He ◽  
Li Na Liu ◽  
Shi Kun Ou

Thispaper presents an experimental study to strengthen an existing bridge usingpre-stressed carbon fiber reinforced polymer (CFRP) and glass fiber reinforced polymer(GFRP) materials. The method using pre-stressed hybrid fiber reinforced polymer(HFRP) to strengthened structural members is an emerging pre-stressed strengtheningtechnology. In this study, experimental data selected from result of staticloading test conducted to hollow slabs with CFRP/GFRP has been compared with specimenswithout strengthening. Test results showed that the strengthening methoddeveloped in this study could effectively reduce the stress in hollow slab,improving the flexural rigidity and inhibiting the concrete from fracture.


2011 ◽  
Vol 18 (1-2) ◽  
pp. 69-77 ◽  
Author(s):  
Sevket Ozden ◽  
Hilal Meydanli Atalay

AbstractThe strength and post-peak performance of reinforced concrete corbels, strengthened with epoxy bonded glass fiber reinforced polymer (GFRP) overlays, were experimentally investigated. The test variables were the corbel shear span to depth ratio, corbel main reinforcement ratio, and the number and orientation of the GFRP fibers. In total, 24 normal strength concrete, one-third scale, corbel specimens, without hoop reinforcement, were tested to failure under quasi-static gravity loading. Test results revealed that GFRP overlays can easily be used for the enhancement of corbel load bearing capacity, depending on the fiber orientation. The main reinforcement ratio and the number of GFRP plies were found to be the two main variables affecting the level of strength gain in the corbel specimens.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Mervin Ealiyas Mathews ◽  
Anand N ◽  
Diana Andrushia A ◽  
Tattukolla Kiran ◽  
Khalifa Al-Jabri

PurposeBuilding elements that are damaged by fire are often strengthened by fiber wrapping techniques. Self-compacting concrete (SCC) is an advanced building material that is widely used in construction due to its ability to flow and pass through congested reinforcement and fill the required areas easily without compaction. The aim of the research work is to examine the flexural behavior of SCC subjected to elevated temperature. This research work examines the effect of natural air cooling (AC) and water cooling (WC) on flexural behavior of M20, M30, M40 and M50 grade fire-affected retro-fitted SCC. The results of the investigation will enable the designers to choose the appropriate repair technique for improving the service life of structures.Design/methodology/approachIn this study, an attempt has been made to evaluate the flexural behavior of fire exposed reinforced SCC beams retrofitted with laminates of carbon fiber reinforced polymer (CFRP), basalt fiber reinforced polymer (BFRP) and glass fiber reinforced polymer (GFRP). Beam specimens were cast with M20, M30, M40 and M50 grades of SCC and heated to 925ºC using an electrical furnace for 60 min duration following ISO 834 standard fire curve. The heated SCC beams were cooled by either natural air or water spraying.FindingsThe reduction in the ultimate load carrying capacity of heated beams was about 42% and 55% for M50 grade specimens that were cooled by air and water, respectively, in comparison with the reference specimens. The increase in the ultimate load was 54%, 38% and 27% for the specimens retrofitted with CFRP, BFRP and GFRP, respectively, compared with the fire-affected specimens cooled by natural air. Water-cooled specimens had shown higher level of damage than the air-cooled specimens. The specimens wrapped with carbon fiber could able to improve the flexural strength than basalt and glass fiber wrapping.Originality/valueSCC, being a high performance concrete, is essential to evaluate the performance under fire conditions. This research work provides the flexural behavior and physical characteristics of SCC subjected to elevated temperature as per ISO rate of heating. In addition attempt has been made to enhance the flexural strength of fire-exposed SCC with wrapping using different fibers. The experimental data will enable the engineers to choose the appropriate material for retrofitting.


Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2532
Author(s):  
Rahima Shabeen Sirajudeen ◽  
Rajesh Sekar

Glass fiber reinforced polymers (GFRP), with their advantage of corrosion resistance, have potential to be used as structural members in civil engineering constructions. Pultruded GFRP angle section trusses could be used instead of steel sections in remote areas and in areas prone to corrosion. The objective of this paper is to study the strength of GFRP angle sections under concentric axial load. Glass fiber reinforced polymer (GFRP) made of E-glass and Isophthalic polyester resin and manufactured by pultrusion process was used for the experimental study. Two GFRP angle sections of size 50 × 50 × 6 mm and 50 × 50 × 4 mm and lengths 500 mm, 750 mm, and 1000 mm were chosen for the study. Further, finite experimental element analysis of the GFRP angle sections was done using ANSYS software and validated with the experimental results. The validated FE model was used for parametric studies varying the slenderness ratio and flange width to thickness ratio (b/t) ratio. It was observed that length of the specimen and thickness influenced the buckling load and buckling mode. An increase in b/t ratio from 8.3 to 12.5 decreases the load carrying capacity by almost 60% at a slenderness ratio of 50.


2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Bo Wen ◽  
Chunfeng Wan ◽  
Lin Liu ◽  
Da Fang ◽  
Caiqian Yang

Fatigue behavior is an important factor for mechanical analysis of concrete members reinforced by basalt fiber reinforced polymer (BFRP) grid and polymer cement mortar (PCM) and plays a critical role in ensuring the safety of reinforced concrete bridges and other structures. In this study, on the basis of the static loading test results of concrete specimens reinforced by BFRP grid and PCM, a series of fatigue tests with different loading levels were conducted on interfaces between BFRP grid and concrete to investigate the fatigue behavior of BFRP grid-concrete interfaces. The test results indicate that with high loading level, the fatigue failure mode of interface is interfacial peeling failure while it transforms to the fatigue fracture of the BFRP grid under low loading level. The fatigue life (S-N) curves of BFRP grid-concrete interface are obtained and fitted in stages according to different failure modes, and the critical point of the two failure modes is pointed out. The relative slip evolution of interface during fatigue is further revealed in different stages with two failure modes, and the law of interface strain is studied with the increase of fatigue times. The relation of effective bonding length of interface and fatigue times is also described.


Sign in / Sign up

Export Citation Format

Share Document