Application Research on Transformed Section Method in Stress Redistribution Deduced by Creep in Concrete Beam Reinforced with FRP

Internal Force ◽

Stress Redistribution ◽

Application Research ◽

Section Method ◽

Height Change ◽

Stress And Deformation

For un-cracked reinforced concrete beam with FRP, the adjusted effective modulus theory (AEMM theory) is applied and the calculation method of internal force and stress redistribution of various materials under creep is given with the transformed section method. A comparative analysis is carried out from height change of the concrete beams, reinforcement ratio, FRP layers and the initial stress. The stress of the bars and FRP will increase over time and the degree of increase will be more obvious with the height of the beam and the reinforcement increased, but the concrete stress will be reduced accordingly. The conclusion plays an important role for the performance evaluation of the long-term stress and deformation of concrete beam reinforced with FRP.

Physical Nonlinear Model Adaptation in Long-Term Structural Health Monitoring: Proposals of Experimental Studies on a Reinforced Concrete Beam

IABSE Symposium Report ◽

10.2749/222137810796063562 ◽

2010 ◽

Vol 97 (8) ◽

pp. 32-38

Author(s):

Martina Schnellenbach-Held ◽

Bjoern Karczewski

Keyword(s):

Reinforced Concrete ◽

Structural Health Monitoring ◽

Nonlinear Model ◽

Health Monitoring ◽

Concrete Beam ◽

Experimental Studies ◽

Model Adaptation ◽

Structural Health

Influence of steel–concrete bond damage on the dynamic stiffness of cracked reinforced concrete beams

Advances in Structural Engineering ◽

10.1177/1369433218761140 ◽

2018 ◽

Vol 21 (13) ◽

pp. 1977-1989 ◽

Cited By ~ 4

Author(s):

Tengfei Xu ◽

Jiantao Huang ◽

Arnaud Castel ◽

Renda Zhao ◽

Cheng Yang

Keyword(s):

Reinforced Concrete ◽

Concrete Beam ◽

Natural Frequencies ◽

Concrete Beams ◽

Dynamic Stiffness ◽

Reinforcing Bar ◽

Sustained Loading ◽

Inertia Model

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.

Prediction Scheme of Torsional Strength of Reinforced Concrete Beam

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.214.306 ◽

2012 ◽

Vol 214 ◽

pp. 306-310

Author(s):

Han Chen Huang

Keyword(s):

Genetic Algorithm ◽

Reinforced Concrete ◽

Concrete Beam ◽

Concrete Beams ◽

Ann Model ◽

Torsional Strength ◽

Prediction Scheme ◽

Optimal Network

This study proposes a artificial neural network with genetic algorithm (GA-ANN) for predicting the torsional strength of reinforced concrete beam. Genetic algorithm is used to the optimal network structure and parameters. A database of the torsional failure of reinforced concrete beams with a rectangular section subjected to pure torsion was obtained from existing literature for analysis. This study compare the predictions of the GA-ANN model with the ACI 318 code used for analyzing the torsional strength of reinforced concrete beam. The results show that the proposed model provides reasonable predictions of the ultimate torsional strength of reinforced concrete beams and offers superior torsion accuracy compared to that of the ACI 318-89 equation.

Uniform loading on the reinforced concrete beam produced by the specific cylinder-shaped rubber bags fully filled with air or water

Advances in Structural Engineering ◽

10.1177/1369433220904006 ◽

2020 ◽

Vol 23 (9) ◽

pp. 1934-1947

Author(s):

Dapeng Chen ◽

Li Chen ◽

Qin Fang ◽

Yuzhou Zheng ◽

Teng Pan

Keyword(s):

Finite Element ◽

Reinforced Concrete ◽

Finite Element Model ◽

Concrete Beam ◽

Concrete Beams ◽

Element Model ◽

Uniform Loading ◽

Air Bag

The bending behavior of reinforced concrete beams under uniform pressure is critical for the research of the blast-resistance performance of structural components under explosive loads. In this study, a bending test of five reinforced concrete beams with the dimensions of 200 mm (width) × 200 mm (depth) × 2500 mm (length) under uniform load produced by a specific cylinder-shaped rubber bag filled with air or water was conducted to investigate their flexural performances. An air bag load was applied to three of the reinforced concrete beams, a water bag load was applied to one reinforced concrete beam, and the remainder beam was subjected to the 4-point bending load. The experimental results highlighted that the air bag and water bag loading methods can be used to effectively apply uniform loads to reinforced concrete beams. Moreover, the stiffness of the air bag was improved by 123% in accordance with the initial pressure increases from 0.15 to 0.45 MPa. In addition, a finite element model of the test loading system was established using ABAQUS/Standard software. Moreover, the critical factors of the air bag loading method were analyzed using the numerical model. The calculated results were found to be in good agreement with the test data. The established finite element model can therefore be used to accurately simulate the action performances of the uniform loading technique using rubber bags filled with air or water.

Experimental Research on Mechanical Behavior of Carbon Fiber Reinforced Concrete Beam

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.641-642.393 ◽

2013 ◽

Vol 641-642 ◽

pp. 393-397

Author(s):

Le Zhou ◽

Jun Wei Wang ◽

Hong Tao Liu

Keyword(s):

Carbon Fiber ◽

Cross Section ◽

Brittle Failure ◽

Concrete Beam ◽

Concrete Beams ◽

Fiber Reinforced Concrete ◽

Test Model ◽

Steel Bar ◽

Fiber Concrete

Based on the cross-section bending of 5 carbon fiber concrete beams, the mechanism of deflection and strain of carbon fiber concrete beam were studied considering the variation of the length of carbon fiber. The experimental results show that the deflection of destruction increased with the increase of the length of the carbon fiber. The carbon fiber can effectively improve the brittle failure of concrete beam, and the stain of concrete accorded with that steel bar at the same height. According to the existing test model, the theoretical calculating formula of CFRC was proposed.

Numerical Analysis of Reinforced Concrete Beam Strengthened with CFRP or GFRP Laminates

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.707.51 ◽

2016 ◽

Vol 707 ◽

pp. 51-59 ◽

Cited By ~ 1

Author(s):

Osama Ahmed Mohamed ◽

Rania Khattab

Keyword(s):

Reinforced Concrete ◽

Concrete Beam ◽

Ultimate Load ◽

Concrete Beams ◽

Fiber Reinforced Polymer ◽

Fiber Reinforced ◽

Reinforced Polymer ◽

Glass Fiber Reinforced

The behaviour of reinforced concrete beam strengthened with Carbon Fiber Reinforced Polymer (CFRP) and Glass fiber reinforced polymer GFRP laminates was investigated using finite element models and the results are presented in this paper. The numerical investigation assessed the effect of the configuration of FRP strengthening laminates on the behaviour of concrete beams. The load-deflection behaviour, and ultimate load of strengthened beam were compared to those of un-strengthened concrete beams. It was shown that using U-shaped FRP sheets increased the ultimate load. The stiffness of the strengthed beam also increased after first yielding of steel reinforcing bars. At was also observed that strengthening beams with FRP laminates to one-fourth of the beam span, modifies the failure of the beam from shear-controlled near the end of the unstrengthened beam, to flexure-controlled near mid-span. CFRP produced better results compared GFRP in terms of the ability to enhance the behavior of strengthenened reinforced concrete beams.

Study on the Flexural Performance of Hybrid-Reinforced Concrete Beams with a New Cathodic Protection System Subjected to Corrosion

Materials ◽

10.3390/ma13010234 ◽

2020 ◽

Vol 13 (1) ◽

pp. 234 ◽

Cited By ~ 2

Author(s):

Yingwu Zhou ◽

Yaowei Zheng ◽

Lili Sui ◽

Biao Hu ◽

Xiaoxu Huang

Keyword(s):

Reinforced Concrete ◽

Concrete Beam ◽

Concrete Beams ◽

Steel Corrosion ◽

Fiber Reinforced Polymer ◽

Flexural Performance ◽

Reinforced Polymer ◽

Steel Bar

Steel corrosion is considered as the main factor for the insufficient durability of concrete structures, especially in the marine environment. In this paper, to further inhibit steel corrosion in a high chloride environment and take advantage of the dual-functional carbon fiber reinforced polymer (CFRP), the impressed current cathodic protection (ICCP) technique was applied to the hybrid-reinforced concrete beam with internally embedded CFRP bars and steel fiber reinforced polymer composite bar (SFCB) as the anode material while the steel bar was compelled to the cathode. The effect of the new ICCP system on the flexural performance of the hybrid-reinforced concrete beam subjected to corrosion was verified experimentally. First, the electricity-accelerated precorrosion test was performed for the steel bar in the hybrid-reinforced beams with a target corrosion ratio of 5%. Then, the dry–wet cycles corrosion was conducted and the ICCP system was activated simultaneously for the hybrid-reinforced concrete beam for 180 days. Finally, the three-point bending experiment was carried out for the hybrid-reinforced concrete beams. The steel bars were taken out from the concrete to quantitatively measure the corrosion ratio after flexural tests. Results showed that the further corrosion of steel bars could be inhibited effectively by the ICCP treatment with the CFRP bar and the SFCB as the anode. Additionally, the ICCP system showed an obvious effect on the flexural behavior of the hybrid-reinforced concrete beams: The crack load and ultimate load, as well as the stiffness, were enhanced notably compared with the beam without ICCP treatment. Compared with the SFCB anode, the ICCP system with the CFRP bar as the anode material was more effective for the hybrid-reinforced concrete beam to prevent the steel corrosion.

Scaled Approach to Designing the Minimum Hybrid Reinforcement of Concrete Beams

Materials ◽

10.3390/ma13225166 ◽

2020 ◽

Vol 13 (22) ◽

pp. 5166

Author(s):

Andrea Gorino ◽

Alessandro Fantilli

Keyword(s):

Reinforced Concrete ◽

Concrete Beam ◽

Concrete Beams ◽

Volume Fraction ◽

Testing Procedure ◽

Fiber Reinforced Concrete ◽

Scale Model ◽

Fiber Volume ◽

Technical Literature

To study the brittle/ductile behavior of concrete beams reinforced with low amounts of rebar and fibers, a new multi-scale model is presented. It is used to predict the flexural response of an ideal Hybrid Reinforced Concrete (HRC) beam in bending, and it is validated with the results of a specific experimental campaign, and some tests available in the technical literature. Both the numerical and the experimental measurements define a linear relationship between the amount of reinforcement and the Ductility Index (DI). The latter is a non-dimensional function depending on the difference between the ultimate load and the effective cracking load of a concrete beam. As a result, a new design-by-testing procedure can be established to determine the minimum reinforcement of HRC elements. It corresponds to DI = 0, and can be considered as a linear combination of the minimum area of rebar (of the same reinforced concrete beam) and the minimum fiber volume fraction (of the same fiber-reinforced concrete beam), respectively.

THE REINFORCED CONCRETE BEAM DEFLECTION AND CRACKING BEHAVIOR WITH ADDITIONAL FIBER STEEL

Proceedings of International Structural Engineering and Construction ◽

10.14455/isec.res.2017.100 ◽

2017 ◽

Vol 4 (1) ◽

Author(s):

Faisal Ananda ◽

Agoes Soehardjono ◽

Achfas Zacoeb ◽

Gunawan Saroji

Keyword(s):

Tensile Strength ◽

Reinforced Concrete ◽

Crack Width ◽

Concrete Beam ◽

Concrete Beams ◽

Beam Deflection ◽

Cracking Behavior ◽

Classic Theory

The classic theory mentions that the assessment of deflection and crack width should be taken to minimize those two behaviors. This research itself has the objective to examine whether the additional fiber steel and increased reinforcement ratio has any significant impact on the deflection and existing crack width. This test used the reinforced concrete beams with a size of 15 cm x 25 cm x 180 cm which placed on a simple pedestal. The test was done gradually in every 108 kg until the reinforced yield reached. The fiber increased from 0%, 1.57%, 3.14% and 4.71% while the performance rebar ratio increased from 2 # 10, 2 # 12, and 2 # 14. The result shows that additional 4.71% of maximum fiber decrease compressive strength and rupture modulus while the tensile strength increased. The additional fiber reached a maximum in 4.71% and the additional diameter of 10 mm, 12 mm, and 14 mm increased the deflections and crack width.

Experiment on the Crack and Deflection of Basalt Fiber Reinforced Concrete Beams

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.1058 ◽

2011 ◽

Vol 243-249 ◽

pp. 1058-1061

Author(s):

Jun Wang ◽

Huan Jun Ye ◽

Zhi Wei Sun ◽

Wei Chen

Keyword(s):

Reinforced Concrete ◽

Concrete Beam ◽

Concrete Beams ◽

Basalt Fiber ◽

Volume Ratio ◽

Fiber Reinforced Concrete ◽

Engineering Practice ◽

Fiber Reinforced

In order to research the influence of basalt fiber on the crack and deflection of the reinforced concrete beams, four basalt fiber reinforced concrete beams with the key parameters of length which were 12mm and 30mm and volume ratio which were 0.1% and 0.2% were designed and made. The test data was obtained through the bending experiment and the comparison with the common reinforced concrete beam. The result shows that it is obvious to control the crack and deflection of the test beams with the increasing of basalt fiber characteristic parameters. The calculation method of the maximum crack width of the basalt fiber reinforced concrete beams were presented based on the method of common concrete beam, which can provide the theoretical basis for the engineering practice.