Moment Capacity of FRP Reinforced Concrete Beam Assessment Based on Centerline Geometry

2013 ◽  
Vol 486 ◽  
pp. 211-216
Author(s):  
Jan Zatloukal ◽  
Petr Konvalinka

The flexural behavior of FRP (Fiber Reinforced Polymer) reinforced concrete beam has been the topic of intensive previous research, because of the spread of use of modern FRP composite materials in the building industry as concrete reinforcement. The behavior of FRP reinforced member is different from the one reinforced with regular steel reinforcement, mainly because of vast difference between moduli of elasticity of FRP composite reinforcement bars and steel. This difference results in the fact that conventional design methods used for years in the field of reinforced concrete structures using steel reinforcement give poor results if attempted use with FRP reinforced structural members. Results of conventional methods are so poor that use of such methods would be dangerous they tend to overestimate load carrying capacity and underestimate deformations both resulting in unsafe predictions. This paper points to formulating easy to use and comprehensible method of predicting moment capacity of FRP reinforced concrete beams subjected to bending loading and validation of the proposed method via set of experiments.

2014 ◽  
Vol 92 ◽  
pp. 74-83 ◽  
Author(s):  
Wanchai Yodsudjai

The applications of using fly ash-based geopolymer as a structural member and a repair materials in reinforced concrete structure was conducted. The optimum mix proportion of fly ash-based geopolymer concrete using for structural beam and fly ash-based geopolymer mortar using for repair material were developed. The flexural behavior of fly ash-based geopolymer reinforced concrete and the durability aspect namely the corrosion of steel reinforcement were investigated using the electrical acceleration. For the repair purpose, the fundamental properties; that is, compressive strength, flexural strength, bonding strength between fly ash-based geopolymer mortar and mortar substrate, setting time and chloride penetration were investigated. Also, the durability of conventional reinforced concrete beam repaired by the fly ash-based geopolymer mortar comparing with the comercial repair mortar was investigated. The behavior of the fly ash-based geopolymer reinforced concrete beam was similar to that of the conventional reinforced concrete beam; however, the corrosion of the steel reinforcement of the fly ash-based geopolymer reinforced concrete beam was higher than that of the conventional reinforced concrete beam. The fundamental properties of the fly ash-based geopolymer mortar were not different from that of the commercial repair materials; however, the durability of the reinforced concrete beam repaired by the fly ash-based geopolymer mortars performed a little lower than that of repaired with the commercial repair motar and also the control reinforced concrete with no repair. As a result, even there will be still a need of improvement there was a good tendency for using the fly ash-based geopolymer as the structural member and the repair materials.


2019 ◽  
Vol 276 ◽  
pp. 01033
Author(s):  
Muhtar ◽  
Sri Murni Dewi ◽  
Wisnumurti ◽  
As’ad Munawir

Bamboo can use at the simple concrete construction because of the tensile strength of its mechanical property. Meanwhile, a slippery surface of the bamboo caused cracks in the bamboo reinforced concrete beam (BRC) not to spread and yield slip failure between a bamboo bar and concrete. Load test at the BRC beam yield humble load capacity. This study aims to improve the capacity and behavior of BRC beam bending by giving waterproof coating, sand, and hose clamp installation. The beam test specimen with the size of 75x150x1100mm made as many as 26 pieces with the variety of reinforcement. The hose clamp used on the bamboo reinforcement varies with a distance of 0 cm, 15 cm, 20 cm, and 25 cm. The testing using a simple beam with two-point loading. The test results show that BRC beams have different bending behavior compared to the steel reinforced concrete beam (SRC).


2006 ◽  
Vol 306-308 ◽  
pp. 1367-1372
Author(s):  
Jeong Hun Nam ◽  
Seung Sik Lee ◽  
Soon Jong Yoon ◽  
Won Sup Jang ◽  
S.K. Cho

FRP composite materials are widely applicable in the construction industries as a load-bearing structural element or a reinforcing and/or repairing materials for the concrete. In this paper, we presented the flexural behavior of steel reinforced concrete beams reinforced with FRP re-bars manufactured by different fibers but the same vinylester resin. Experimental investigation pertaining to the load-deflection and load-strain characteristics of steel reinforced concrete beams reinforced with FRP re-bars with garnet coated surface is presented and the theoretical prediction is also conducted. In the investigation, the effects of FRP re-bar reinforcement in addition to the steel reinforcement are estimated. The experimental results are compared with theoretical predictions. Good agreements are observed.


Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1137 ◽  
Author(s):  
Jongho Park ◽  
Sun-Kyu Park ◽  
Sungnam Hong

In this study, nine specimens were experimentally tested to analyze the strengthening efficiency of textile-reinforced mortar (TRM) and the difference in flexural behavior between prestressed and non-prestressed TRM-strengthened reinforced concrete beam. The test results show that TRM strengthening improves the flexural strength of TRM-strengthened reinforced concrete beams with alkali-resistant-(AR-) glass textile as well as that with carbon textile. However, in the case of textile prestressing, the strengthening efficiency for flexural strength of the AR-glass textile was higher than that of the carbon textile. The flexural stiffness of AR-glass textiles increased when prestressing was introduced and the use of carbon textiles can be advantageous to reduce the decreasing ratio of flexural stiffness as the load increased. In the failure mode, textile prestressing prevents the damage of textiles effectively owing to the crack and induces the debonding of the TRM.


2014 ◽  
Vol 507 ◽  
pp. 306-310 ◽  
Author(s):  
Bin Jia ◽  
Jin Xue ◽  
Jun Mo ◽  
Chun Tao Zhang

Abstract. In the view of the project problem that concrete strength grade is lower than C15in reinforced concrete beam, we consider a composite technology strengthened with CFRP, and do some monotonic loading experiments on these beams with eight different methods, and discuss the beam force behavior including ultimate bearing capacity, failure model and crack propagation. This paper finds out that the composite reinforced scheme, which with ticking trough, planting steel displaces concrete and gluing and then pasting CFRP, has a remarkable improvement than pasting CFRP immediately, and that there is a high coherence workability in the old and new concrete, so we can give full play to their role as the CFRP high strength.


2011 ◽  
Vol 250-253 ◽  
pp. 1478-1482
Author(s):  
Zhi Juan Sun ◽  
Chao He Chen ◽  
Ming Jin Chu ◽  
Peng Feng

In order to improve the durability of reinforced concrete member, fiber reinforced polymer (FRP)-reinforced concrete member is introduces. Monotonic loading was applied to a reinforced concrete beam and FRP-reinforced concrete beam, in order to investigate the failure progress and characteristics of FRP-reinforced concrete beam.. The presenting study provide a basis for improving the design method for FRP-reinforced concrete member.


2013 ◽  
Vol 6 (1) ◽  
pp. 36-49
Author(s):  
Ali Sabah AL-Amili

In this work aims at studying the influence of steel plate on the deflection of self- compacted reinforced concrete beams was investigated experimentally in this study to know the flexural behavior of these beams. Eight simply supported reinforced concrete beam were tested under the action of two point loads .The deflections of the beams with and without plate are measured. The steel plates of thickness (3 mm) with dimensions ( 170 × 350 mm) were used. These plates were sticked on the concrete beams using epoxy. The steel plate inside the beam was sticked with and without epoxy (epoxy type EP), while the beams were taken with and without opening (10 mm diameter). The results show that the plate increased the capacity of the beam by increased the value of failure load. Hence, the beam with internal plate with epoxy increased the failure load by 34.2% than beam without plate , and 24.6% than beam with internal plate without epoxy , and 19.7% than beam with external plate with epoxy .


2021 ◽  
Vol 9 (ICRIE) ◽  
Author(s):  
Ali I. Salahaldin ◽  
◽  
Muyasser M. Jomaa’h ◽  
Dlovan M. Naser ◽  
◽  
...  

One of the most common methods of strengthening, rehabilitation, or repairing of structural lightweight concrete (LWC) elements is the external carbon fiber reinforced polymer (CFRP) strips. This paper presents an experimental study on the flexural behavior of reinforced concrete beams which comprise lightweight aggregate concrete, in different proportions, strengthened by CFRP sheets. The experimental program included six specimens with a 1500mm effective span. Two of the specimens were normal concrete beams. Another two samples were lightweight beams with a 50% aggregate replacement with pumice. The last two specimens were lightweight concrete beams with a 75% aggregate replacement with pumice. These beams were casted and tested twice under a two-point load application, once before strengthening and the other after that. The experimental results show that full strengthening of the beams along with their entire length, increase in load-carrying capacity by 75%, 113%, and 107% for normal concrete beam, (50% aggregate replacement) LWC beam, and (75% aggregate replacement) LWC beam respectively. While the middle-third strengthening of the beams shows an increase in load-carrying capacity by 64%, 72%, and 57% for normal concrete beam, (50% aggregate replacement) LWC aggregate beam, and (75% aggregate replacement) LWC beam respectively. The strength of the two types of LWC beams was almost the same and it is about 85% of the concrete beam with normal weight.


2018 ◽  
Vol 21 (13) ◽  
pp. 1977-1989 ◽  
Author(s):  
Tengfei Xu ◽  
Jiantao Huang ◽  
Arnaud Castel ◽  
Renda Zhao ◽  
Cheng Yang

In this article, experiments focusing at the influence of steel–concrete bond damage on the dynamic stiffness of cracked reinforced concrete beams are reported. In these experiments, the bond between concrete and reinforcing bar was damaged using appreciate flexural loads. The static stiffness of cracked reinforced concrete beam was assessed using the measured load–deflection response under cycles of loading and unloading, and the dynamic stiffness was analyzed using the measured natural frequencies with and without sustained loading. Average moment of inertia model (Castel et al. model) for cracked reinforced beams by taking into account the respective effect of bending cracks (primary cracks) and the steel–concrete bond damage (interfacial microcracks) was adopted to calculate the static load–deflection response and the natural frequencies of the tested beams. The experimental results and the comparison between measured and calculated natural frequencies show that localized steel–concrete bond damage does not influence remarkably the dynamic stiffness and the natural frequencies both with and without sustained loading applied. Castel et al. model can be used to calculate the dynamic stiffness of cracked reinforced concrete beam by neglecting the effect of interfacial microcracks.


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