scholarly journals Review on Effect of Corrosion on Flexure, Shear and Torsional Strength of Reinforced Concrete Beam

Author(s):  
Abhinav Chouhan ◽  
Nikhil Pitale

With the increase in demand for construction materials, man has improved a lot in the construction techniques of structures. Reinforced concrete beams are normally designed as under reinforced to provide ductile behavior such as the tensile moment of resistance. In coastal environment reinforcement corrosion is an obvious cause of deterioration of concrete structure, which affects the durability and service of reinforced concrete structure. Structural stability is majorly influenced by strength of concrete. Torsional strength is a measure of the shear strength of concrete, in other words it is a measure of a resistance against failure in twisting. The main aim of this study is to analyze the flexural, shear & torsional strength, experimentally; of corroded beams using Ordinary Portland cement. Accelerated corrosion technique was adopted to corrode the beam experimentally. We have used varying percentage of corrosion as 0%, 2.5%, 5% and 7.5%. Change in strength of RC beams is studied for varying percentage of corrosion. Beam specimens are prepared using M20 grade concrete for OPC. Beam specimens casted are tested in UTM for flexure and shear. Specially prepared loading setup is used for torsional strength test.

2012 ◽  
Vol 214 ◽  
pp. 306-310
Author(s):  
Han Chen Huang

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.


2011 ◽  
Vol 250-253 ◽  
pp. 2857-2860 ◽  
Author(s):  
Yu Zhuo Wang ◽  
Chuang Guo Fu

Prestressed steel reinforced concrete structure, compared with other concrete structure has its unique advantages. So it is mainly used in large span and conversion layers. With the popularization of this structure,more attention should be payed on fire resistance performance. On the basis of reasonable assume,two steps model is used as concrete high strength calculation model. Simplified intensity decreased curve is used as rebar,steel and prestressed. Two ultimate bearing capacity formulas of prestressed steel reinforced concrete beam are established. One is for the beam whose tensile area is under fire, the other is for the beam whose compression area is under fire. Prestressed steel reinforced concrete structure has both prestressed concrete structure’s advantages and steel reinforced concrete structure ’s advantage. Steel reinforced concrete is used to improve the bearing capacity of the structure. Prestressed steel is used to improve the ultimate state of structure’s performance during normal use. Thereby structure’s performance is better to play. There are many similarities between prestressed steel reinforced concrete structure and steel reinforced concrete structure about fire resistance performance. Because of prestressed steel reinforced concrete structure’s own characteristics, there are still many problems about fire resistance. This paper mainly presented bending terminal bearing capacity of prestressed steel reinforced concrete beam under fire. Established simplified formulae for calculation, it is meet the engineering accuracy requirement.


2022 ◽  
Vol 2148 (1) ◽  
pp. 012034
Author(s):  
Yihong Hong

Abstract Reinforced concrete structure is widely used in building structure because of its unique physical and mechanic properties, but with the increase of service life, there will be different degrees of damage in the structures. In this paper, combined with the test beam, a model of reinforced concrete beam strengthened with CFRP is established by Using ANSYS finite element software, nonlinear finite element analysis is carried out on the whole process of yield, cracking and destruction of the test beam under secondary load, while different working states of CFRP sheets were simulated by the life and death unit. The results show that the bending performance of reinforced concrete (RC) beams strengthened with CFRP can be predicted by selecting the finite element analysis model rationally.


2013 ◽  
Vol 712-715 ◽  
pp. 966-969 ◽  
Author(s):  
Ze Bao Kan ◽  
Yan Ru Li

The present status of reinforced concrete structure confined by FRP is introduced, and the recent technical researches of reinforced concrete beams and columns confined by BFRP are summarized. Based on those researches, the mechanical properties and calculation models are analyzed. At the same time, the seismic performance of reinforced concrete beams and columns confined by BFRP is also explored.


2015 ◽  
Vol 754-755 ◽  
pp. 373-377 ◽  
Author(s):  
Mustaqqim Abdul Rahim ◽  
Zuhayr Md Ghazaly ◽  
Muhammad Azizi Azizan ◽  
Fazdliel Aswad Ibrahim ◽  
Norlia Mohamad Ibrahim ◽  
...  

In the normal practice in the reinforced concrete design, the main reinforcement steel bar and links was used to fabricate the concrete structure. However new materials such as steel fiber has been introduced as the reinforcement to the reinforced concrete structure [1]. Nowadays, the application of fiber in concrete increase slightly as an engineering material demands. Fibers have distinctive of geometry, size and material. The characteristics and properties of fiber influence the properties concrete. Steel, glass and synthetic fibers were used in concrete in 1960s because of the difficulty to handle the asbestos fiber [2].


2005 ◽  
Vol 293-294 ◽  
pp. 695-702 ◽  
Author(s):  
Rogerio Bairrao ◽  
Marcin Chrzanowski ◽  
Joaquim Duque ◽  
Pawel Latus

In several situations the failure of a reinforced concrete structure is preceded by a gradual deterioration of the materials which can be recognised by measuring the change of their physical properties [1]. The main purpose of the destructive tests described in the present paper was to obtain an evaluation of the damage evolution in a reinforced concrete beam, submitted to harmonic displacements imposed by means of a shaking table. A reinforced concrete beam, with two different spans, was designed to sustain a static load of a mass located at the centre of the longer span. Ten identical specimens were prepared and tested at the LNEC (National Laboratory for Civil Engineering, Lisbon) shaking table facility [2]. This paper presents tests, which have been performed in the frame of the European Commission programme ECOEST/PECO (European Consortium of Earthquake Shaking Tables / Central and Eastern European Countries extension). The beams were fixed to the shaking table and submitted to a sinusoidal displacement in the vertical direction, with a pre-established duration and constant amplitude. The tests were carried out by successive stages of increasing amplitudes, until the collapse of each beam was reached. The tests aimed to give an evaluation of the loading history influence on the occurrence of the critical state. During the tests, displacements and accelerations were continuously recorded at several points of the structures, along with ultrasonic measurements taken at different directions, before and after each successive stage. In the present paper the design of the specimens is given. The instrumentation plan, the test setup and the test procedure are also described. Finally, the most relevant results are shown followed by the formulation of a global damage law to predict the limit state of the beams.


2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
Xiwu Zhou ◽  
Runcheng Zhang ◽  
Ruisheng Xiong ◽  
Guoxue Zhang ◽  
Xiangyu Wang

The reinforced concrete structure of a port wharf is affected by steel corrosion and ship docking impact. Replacing an ordinary steel bar with a stainless steel bar can solve the corrosion problem of the steel bar while ensuring the bearing capacity of the structure. However, the research on impact resistance of stainless steel-reinforced concrete structure is not perfect. In this paper, impact mechanical properties of reinforced concrete beams before and after equal strength replacement of stainless steel bars are analyzed by theoretical analysis and drop hammer impact test, and the possibility and applicable scope of equal strength replacement of stainless steel bars are put forward. The results indicated the following: (1) when the reinforcement ratios were small (0.21% to 1.32%), the stainless steel-reinforced concrete beams with equal strength were able to effectively reduce the stiffness losses of the beams undergoing impact loads, as well as improve the elastic resilience abilities, and reduce the structural damages. Therefore, the corrosion and impact problems of reinforcements could be solved by replacing ordinary reinforcements with stainless steel reinforcements and (2) when the reinforcement ratios were large (1.32% to 2.57%), the shear failures of the stainless steel-reinforced concrete beams were observed to be relatively serious, and the impact resistance performances had worsened. The research results provide technical support for the engineering application of stainless steel-reinforced concrete structure design.


2012 ◽  
Vol 151 ◽  
pp. 286-290 ◽  
Author(s):  
Ke Wei Ding ◽  
Ai Yu Yang

With economic prosperity and social development, various kinds of unconventional concrete structure increases day by day, steel reinforced concrete structure has been widely used. The paper demonstrated the Hefei Yangtze-crossing Campaign Memorial Project, by comparing theoretical results with site monitoring data analysis results, summarized the variation of stress and strain distribution in the cantilever truss steel reinforced concrete beam structure. The main content of this paper introduced the study of steel reinforced concrete with the project to make conclusions that they would be significance to apply in the future similar projects for guidance and reference.


Author(s):  
Shrabanee Giri

Corrosion of reinforcement in concrete affects the strength and durability of reinforced concrete structure. Monitoring and maintenance of concrete structure throughout the service life prevent the ingress of corrosion at the initial stage. Half-cell potential meter was developed and fabricated to monitor the corrosion potential of reinforcement in a M25 grade concrete. Half-cell potential test and accelerated corrosion test has been carried out in marine environment of 3.5% of NaCl solution. The potential behaviour of specimen subjected to accelerated corrosion is studied throughout the test period. The results were obtained in terms of current flow behaviour and weight loss. Obtained results has been analyzed graphically and a comparative analysis has been carried out to know the rate of corrosion occurred in the specimen by accelerated corrosion test and half-cell potential test. Obtained results clearly indicates that the potential behaviour value increases with increase in time from 160 mV on day 1 to 949 mV on day 5. In the other way the compressive strength value for corroded specimen is lesser than the controlled specimen subjected to accelerated corrosion.


Teras Jurnal ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 351
Author(s):  
Zahra Amalia ◽  
Taufiq Saidi ◽  
Taufiq Saidi ◽  
Teuku Budi Aulia ◽  
Teuku Budi Aulia ◽  
...  

<p align="center"><strong>Abstrak</strong></p><p class="11daftarpustaka"> </p><p>Korosi pada struktur beton betulang dapat mengurangi kinerja struktur dan umur layannya karena volume tulangan yang berkurang. Besarnya jumlah korosi yang dipengaruhi oleh laju korosi dapat digambarkan melalui besarnya densitas arus yang terjadi. Jumlah korosi yang terjadi mempengaruhi perilaku retak pada beton bertulang, oleh karen itu, pada studi ini dilakukan uji eksperimental untuk mengevaluasi pengaruh densitas arus terhadap perilaku retak permukaan beton dari struktur beton bertulang yang mengalami korosi tulangan. Pengujian dilakukan dengan mengaplikasikan variasi densitas arus yaitu 900 µA/cm<sup>2</sup>, 500 µA/cm<sup>2</sup>, 200 µA/cm<sup>2</sup> and 100 µA/cm<sup>2</sup> pada pengujian korosi secara elektrik menggunakan larutan NaCl sebagai elektrolit untuk menghasilkan ion Cl<sup>-</sup>. Benda uji yang digunakan adalah balok dengan luas penampang 150x150 mm<sup>2</sup> dan panjang benda uji 300 mm. Tulangan baja diameter 19 mm digunakan pada tengah penampang. Hasil pengujian menunjukkan bahwa perilaku retak dari beton bertulang yang mengalami korosi pada tulangannya memiliki kurva yang bilinear. Selain itu, hasil pengujian menunjukkan bahwa densitas arus yang rendah memiliki kecepatan retak permukaan beton yang lebih tinggi jika dibandingkan dengan benda uji dengan menggunakan densitas arus yang tinggi.</p><p> </p><p>Kata kunci<em>: korosi, beton bertulang, produk korosi, retak, densitas arus</em></p><p align="center"><strong> </strong></p><p align="center"><strong>Abstract</strong></p><p class="Abstract"> </p><p>Corrosion in reinforced concrete structure can reduce structure performance and its service life due to rebar mass loss. Corrosion amount influenced by corrosion rate can be figured out by using current density. Corrosion amount influences the crack behavior of reinforced concrete, therefore, in this study, experimental study was performed to evaluate the effect of current density to surface concrete cracking behavior of corroded reinforced concrete structure. Accelerated corrosion test tests were conducted with various current density. It was 900 µA/cm2, 500 µA/cm2, 200 µA/cm2 and 100 µA/cm2. NaCl solution was used as electrolyte to produce ion Cl<sup>-</sup>. The specimens were beam with cross section area 150x150 mm<sup>2</sup> and 300 mm in length. Rebar with diameter 19 mm was applied in the center of specimen. The results showed that cracking behavior of corroded rebar has bilinear curve that shows the effect of corrosion products movement through cracks. Furthermore, lower corrosion rate has higher cracking speed than higher corrosion rate.</p><p> </p><p>Keywords: <em>corrosion, reinforced concrete, corrosion products, cracking, current density</em></p>


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