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Effects of Elastic Modulus on Behavior of Polymer Coated Fiber Modified Short Concrete Beams
Kasim Korkmaz,
Salih Kocak,
Mohamed El Gafy,
Erkan Boztas
Issue:
Volume 3, Issue 1, June 2019
Pages:
1-9
Received:
14 October 2018
Accepted:
1 November 2018
Published:
29 January 2019
Abstract: Polymers have been one of the mostly and effectively used materials all over the world recently. They have been gaining popularity for various purposes in the concrete industry last couple of decades as well. They have the ability to increase the strength and durability of the concrete products. Moreover, polymers in concrete industry can also be considered as a sustainable product since they achieve the requirements of the consumers without adversely affecting the environment, health and the economy. Fiber-modified short beams are structural members commonly used in construction industry. To enhance their physical properties, various methods have been developed; however, most of them have been considered costly and time consuming. In this study, it was concluded that one major physical property, strength, of fiber-modified concrete short beams could be improved by using polymer as a coating material. Hence, the capacity and probably the service life of those beams could be improved. Furthermore, proper polymer coating may reduce the maintenance costs. In this study, polymer coating is applied for fiber modified short concrete beams. The change in modulus of elasticity was investigated as the identifying parameter between various coated short beams since it is an important parameter in the design and analysis processes of the beams. The elastic moduli for various regions of the world were derived from compressive strength results. The maximum deflection values were computed for each region and each polymer coating as well. Finally, the most effective polymer type and coating were discovered according to the maximum deflections obtained for simply supported beam approach.
Abstract: Polymers have been one of the mostly and effectively used materials all over the world recently. They have been gaining popularity for various purposes in the concrete industry last couple of decades as well. They have the ability to increase the strength and durability of the concrete products. Moreover, polymers in concrete industry can also be c...
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Investigating the Effective Impact of Permanent Pavement in Sustainable Development in Developing Countries (From the Point of View of Material Valuation and Prediction of Performance)
Issue:
Volume 3, Issue 1, June 2019
Pages:
10-15
Received:
15 April 2019
Accepted:
23 May 2019
Published:
5 June 2019
Abstract: Assuming that the road infrastructure has been implemented in accordance with specifications and standards, poor adhesion between the two layers of asphalt mix can be a significant cause of pavement problems. The general problem observed with the weak adhesion between the layers is the slip failure. Slipping disruption in areas where transport acceleration increases, in areas where acceleration decreases or may occur in bumps. One of the criteria and a test method for measuring adhesion resistance between the hot mix asphalt layers is needed to improve the surface finish. The main objective of this study is to determine the effect of reducing the coefficient of friction between asphalt layers in the displacement of asphaltic layers. Because performing experimental experiments in the country is a deterrent to this goal, the use of analytical and numerical methods has been shown to play an important role in conducting studies. Therefore, in this paper, using vehicle simulation in ABAQUS software and analyzes, it has been found that decreasing the coefficient of friction (adhesion reduction) increases the interlayer deformation, which causes the surface of the pavement to fail. Three different thicknesses for asphalt cladding, including 4, 6, and 7 centimeters, and three different thicknesses for roller concrete layers of 18, 20 and 22 centimeters are used. Modeling and analysis of pavements with finite element method has been performed and the depth of the asphalt and tensile strain slope is calculated at the maximum level. The results show that the type of asphalt mix has a high impact on the amount of sloping and tensile strain at the maximum level. So that under different conditions it is estimated to be about 2-3 times in the amount of rotation at the surface. Also, the amount of groove and strain in the middle of the procedure is increased by a thickness of 11% the thickness of the roller concrete thickness has not changed, but the surface strain has been reduced by 9%.
Abstract: Assuming that the road infrastructure has been implemented in accordance with specifications and standards, poor adhesion between the two layers of asphalt mix can be a significant cause of pavement problems. The general problem observed with the weak adhesion between the layers is the slip failure. Slipping disruption in areas where transport acce...
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A Statistical Analysis of the Distribution of the Chloride Threshold with Relation to Steel-concrete Interface
Issue:
Volume 3, Issue 1, June 2019
Pages:
16-22
Received:
13 August 2019
Accepted:
30 August 2019
Published:
18 September 2019
Abstract: A wide variation of chloride thresholds can be found in the literature. Possible causes for this variation, which were mentioned are: method of threshold determination, cement chemistry, and concrete microstructure. Regardless of the reasons for these variations, a probabilistic method can be used to ensure the durability of reinforced concrete structures for a specific period. A probabilistic method gives a threshold for design for given required confidence. A former research analyzed the micro-structure of concrete around steel rebar, by means of BSE automated image analysis, and the chloride threshold. The research found a statistical significant correlation between the maximal distance of steel from the closest concrete solid on the rebar perimeter and the chloride threshold. Theory of statistics of extreme values state, that the distribution of maxima data is bonded to be general extreme value distribution (GEVD). Re-analysis of the data from the abovementioned research found that as expected from the theory of statistics, the maximum steel-concrete distance distributed according to GEVD. Therefore, since the chloride threshold depends on the steel-concrete distance, its distribution is bonded to the GEVD. The analysis in this paper show that the received chloride threshold is GEVD as the theory predicted. From the theoretical point of view, GEVD may be the distribution of many other corrosion processes. The recognition of GEVD as the correct distribution for describing corrosion initiation in reinforced concrete (RC) structures, can enable more accurate planning for corrosion protection.
Abstract: A wide variation of chloride thresholds can be found in the literature. Possible causes for this variation, which were mentioned are: method of threshold determination, cement chemistry, and concrete microstructure. Regardless of the reasons for these variations, a probabilistic method can be used to ensure the durability of reinforced concrete str...
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