scholarly journals Self-Fibers Compacting Concrete Properties Reinforced with Propylene Fibers

2021 ◽  
Vol 28 (1) ◽  
pp. 64-72
Author(s):  
Jawad Ahmad ◽  
Fahid Aslam ◽  
Osama Zaid ◽  
Rayed Alyousef ◽  
Hisham Alabduljabbar ◽  
...  

Abstract Self-Consolidating Concrete (SCC) has also brittle characteristics. This is unacceptable for any construction industry. The addition of fibers is one of the most common methods to enhance the tensile strength of concrete. Fiber controls the cracking phenomena and enhances the energy absorption capability of the concrete. On the other hand, the addition of fibers has a negative impact on the workability of fresh concrete. In this paper, a detailed study on the influence of Propylene fibers (PP) on the fresh properties of SCC was carried out. PFs were added into concrete mixes in a proportion of 1.0%, 2.0%, 3.0%, and 4.0% by weight of cement to offset its undesirable brittle nature and enhance its tensile strength. The fresh characteristics were evaluated based on its passing ability, flowability using, Slump flow, Slump T50 Spread time, L-Box and V-funnel tests as well as mechanical performance (compressive and split tensile strength) were also evaluated at 7,14 and 28 days curing. Test results indicate that the passing and filling ability decreased as the substitution ratio of PP increased. Besides, the test result indicates that strength was increased up to 2.0% addition of PP and then decrease gradually.

Self-compacting concrete is one that is flow able by its own. The SCC is suitable for placing in dense reinforcement structures. It is a new generation performance concrete known for its outstanding deformity and high resistance to bleeding. The concrete is frail material which is comparatively tough in compression but fragile in tension. The tensile strength of concrete is improved by addition of fibers in the concrete mix. The addition of such fibers has negative consequence on the workability of concrete. Various types of fibers are used in concrete to provide the higher flexural strength and better tensile strength. In this research steel fibers are used to provide a better strength as compared with normal reinforced concrete. Steel fiber in SCC significantly improves its flexural strength, improved tensile properties, reduce cracking and improve durability. In this research the investigation of steel fiber in SCC to enhance the strength properties of SCC. The objective of the study was to determine different properties of SCC with steel fiber at different proportions. The experimental investigation was took on the freshly mixed and hardened properties of SCC of various mix with the different variations of fiber 0.25%, 0.50%, 0.75% and 1% by using Viscosity Modified Agent (VMA) 1.5% of cement material by using M25 grade of concrete. In this research a series of tests were carried out for workability like slump cone test, U funnel, V funnel, L box test on SCC to check freshly mix properties like flow-ability, filling-ability, and passing-ability and hardened properties like compressive strength, split-tensile strength and flexural strength respectively and test were conducted at the age of 7Days, 14Days, 28Days on the SCC. The advantage of adding steel fiber in self-compacting concrete is that it enhances its overall strength.


Self-compacting concrete is gaining importance in recent years due to its highest versatility in replacing compacting equipment and there by reducing the constructional flaws. The only limitation of SCC of compromising with strength has been challenged by the addition of steel fibers in this paper. In this research work two types of steel fibers such as crimped type and hook end type are utilized in various proportions such as 0.4%,0.8%, 1.0% and 1.25%. SCC mandatory tests such as Flowing ability, filling ability and passing ability were determined and then the mechanical properties such as compressive strength and split tensile strength have been determined. Results show the unique variation with reference to the different type of fiber and different volume of fiber. This unleashes a lot of scope in the field of Fiber reinforced Self compacting concrete


This research work has been investigated the agriculture solid waste of sugarcane bagasse ash (SCBA) materials replacing Portland cement and produces the assured quality of concrete. The current research work for various mixes of experimental test results shows the higher compressive strength was 37.51MPa at 28-days, 38.10 MPa at 56-days, the best mix consisting of SCBA (wet sieving method) content up to 15% (by weight of binding materials) along with 1.5% of waste tin fibers and also an excellent improvement trend was noted in flexural rigidity of concrete to addition of tin fibers shows the higher bending stress for all mixes except reference as well as more than 15% of SCBA concrete at different curing days. However, this study focused on the indirect measurement of tensile strength in SCBA concrete obtained the higher split tensile strength was 3.75MPa at 28-days, 3.95MPa at 56-days. It is concluded based on the various test results for different curing days the optimum replacement level of SCBA up to 15% of Portland cement was fixed and achieve the target strength of M25 grade of Portland cement concrete at 28 days.


2019 ◽  
Vol 292 ◽  
pp. 9-14 ◽  
Author(s):  
Oldrich Sucharda ◽  
Vlastimil Bilek

Concrete is typical composite material and its properties can be very variable. Material properties are also influenced with the technology of processing, manufacturing and treatment after concreting. Reinforcement in form of fibers is often added for improving tensile strength. This paper deals with specific testing of fibre concrete. Test results of series of specimens are presented for selected transport concrete composition, which is reinforced with amount of fibers 25, 50, 75 kg / m3. Fibers were added directly into the into the concrete mixer in the factory. Each series includes more than 25 test samples. The tests include the compressive strength of a cube and cylindrical, testing of modulus of elasticity, and the split tensile strength in the direction perpendicular to and parallel to the filling. Within the research project also a few types of bending tests were performed. Four variants of bending test that vary in span of 500 or 600 mm, samples with and without a notch, and in a three- / four-point configuration. As a summary, broader evaluation and functional dependencies are derived.


Author(s):  
Mônica Navarini Kurz ◽  
Charlei Marcelo Paliga ◽  
Ariela da Silva Torres

RESUMO: O setor da construção civil vem absorvendo resíduos e transformando-os em componentes para utilização nas construções, especialmente através da incorporação em materiais como argamassas e concretos. Com o crescente número de veículos automotivos, ocorreu um aumento na produção de pneus e, consequentemente, de seus resíduos. Portanto, o presente estudo tem o objetivo de avaliar o melhor teor de substituição de agregado miúdo por resíduo de borracha em argamassa de cimento e cal, a partir da comparação com uma argamassa de referência, analisando o comportamento físico e mecânico. Para verificar a melhor relação de substituição, os ensaios foram realizados em argamassa referência (traço 1:2:9) e em argamassas com resíduos nas proporções de 2,5%, 5%, 10% e 15% de substituição de areia por borracha. Para caracterização das argamassas foram realizados ensaios de índice de consistência, resistência à compressão axial, resistência à tração por compressão diametral, absorção por capilaridade e absorção por imersão. Os resultados indicam que nas argamassas com resíduo ocorreu um aumento na relação a/c para se manter a trabalhabilidade e um decréscimo nas resistências. Além de, uma diminuição na absorção por capilaridade e um aumento na absorção por imersão. Apesar de provocar mudanças no comportamento da argamassa, aponta-se o uso desse resíduo como alternativa viável, tanto ambiental quanto de desempenho.ABSTRACT: The construction industry has been absorbing and transforming them into components for use in construction, especially through the incorporation of materials such as mortars and concretes. With the increasing number of automotive vehicles, there has been an increase in the production of tires and, consequently, of their waste. Therefore, the present study has the objective of evaluating the best content of substitution of small aggregate by rubber residue in cement and lime mortar, from the comparison with a reference mortar, analyzing the physical and mechanical behavior. To verify the best substitution ratio, the tests were performed in reference mortar (trace 1:2:9) and mortar with residuals in the proportions of 2.5%, 5%, 10% and 15% of Sand for rubber. To characterize the mortars, tests of consistency index, axial compression strength, tensile strength by diametrical compression, capillary absorption and immersion absorption were performed. The results indicate that in the mortars with residue an increase in the w/c ratio was observed to maintain the workability and a decrease in the resistances. In addition to, a decrease in capillary absorption and an increase in absorption by immersion. Although it causes changes in mortar behavior, the use of this residue is indicated as a viable alternative, both environmental and performance.


Author(s):  
Afzal Basha Syed ◽  
Jayarami Reddy B ◽  
Sashidhar C

In present era, high-strength concrete is progressively utilized in modern concrete technology and particularly in the construction of elevated structures. This examination has been directed to explore the properties of high-strength concrete that was delivered by using stone powder (SP) as an option of extent on sand after being processed. The aim of the research is to study the effect of replacement of sand with stone powder and substitution of cement with mineral admixtures (GGBS & Zeolite) on the mechanical properties of high strength concrete. The test results showed clear improvement in compression and split tensile nature of concrete by using stone powder and mineral admixtures together in concrete. The increment in the magnitude of compressive strength and split tensile strength are comparable with conventional concrete.


2012 ◽  
Vol 602-604 ◽  
pp. 938-942 ◽  
Author(s):  
Wai Ching Tang

In this paper, the fresh properties of self-compacting concrete (SCC) using recycled coarse aggregate (RCA) were evaluated. Five types of SCC mixtures were made, where the percentage of substitution of natural coarse aggregate by RCA was 0, 25, 50, 75 and 100%. The cement content, water to binder (W/B) ratio and Superplasticizer dosage were kept the same for all mixes. The effects of RCA on the key fresh properties such as filling ability, passing ability, and segregation resistance of SCC were investigated by conducting several fresh concrete tests included slump-flow, L-box, and sieve stability tests. The overall test results suggest that RCA can be used to produce SCC substituting up to 100% natural coarse aggregates without affecting the key fresh properties of concrete.


2011 ◽  
Vol 284-286 ◽  
pp. 1732-1735
Author(s):  
Xiao Ling Xie ◽  
Wen Hai Li ◽  
Ying Hui Wei

The samples were modified by using chlorinated polyethylene (CPE) to increase the toughness and using dioctyl phthalate (DOP) to increase the plasticity. The tensile strength and breaking elongation of the samples were studied by changing the chlorinated polyethylene (CPE) and dioctyl phthalate (DOP) contents and the hot-pressing temperature. It was shown by the test results that, with the increase of chlorinated polyethylene (CPE) and dioctyl phthalate (DOP) contents, the tensile strength of the samples was decreased while the breaking elongation was increased. By increasing the hot-pressing temperature, the blending effect between polyvinyl chloride (PVC) and chlorinated polyethylene (CPE) as well as the mechanical performance of the samples were increased, however, over-high hot-pressing temperature would result in plasticizer precipitation.


2019 ◽  
Vol 8 (3) ◽  
pp. 7736-7739 ◽  

This paper studies the effect of incorporating metakaolin on the mechanical properties of high grade concrete. Three different metakaolins calcined at different temperature and durations were used to make concrete specimens. Three different concrete mixtures were characterized using 20% metakaolin in place of cement. A normal concrete mix was also made for comparison purpose. The compressive strength test, split tensile test and flexural strength tests were conducted on the specimens. The compressive strength test results showed that all the metakaolin incorporated concrete specimens exhibited higher compressive strength and performed better than normal concrete at all the days of curing. The rate of strength development of all the mixes was also studied. The study revealed that all the three different metakaolin incorporated mixtures had different rate of strength development for all the days of hydration (3, 7,14, 28, 56 and 90), indicating that all the metakaolins possessed different rate of pozzolanic reactivity. Further, from the analysis of the test results, it was concluded that the variation in the rate of strength development is due to the differences in the temperature and duration at which they were manufactured. The results of split tensile strength test and the flexural strength test conducted on the specimens, supported the conclusions drawn from the results of compressive strength test. The paper also discusses, the rate of development of compressive strength and the pozzolanic behaviour of the metakaolins in light of their parameters of calcination and physical properties such as amorphousness and particle size. This paper has been written with a view to make the potential of metakaolin available to the construction industry at large


2012 ◽  
Vol 6 (1) ◽  
pp. 38-47 ◽  
Author(s):  
Wu-Jian Long ◽  
Kamal Henri Khayat ◽  
Feng Xing

Self-consolidating concrete (SCC) mixtures designated for precast, prestressed applications should be highly workable to flow easily through restricted spacing and completely encapsulate reinforcements without any mechanical vibration. Key workability characteristics of SCC can be described in terms of filling ability, passing ability, and resistance to segregation. These properties are typically characterized by data that relate to specific testing methods. In general, these methods include the components required for evaluating simultaneously filling ability, passing ability, and resistance to segregation, since these properties are rather interrelated. In this investigation, 33 SCC mixtures made with various mixture proportioning parameters, including maximum size and type of aggregate, type and content of binder, and w/cm were evaluated. The mixtures were prepared using crushed aggregate and gravel of three different nominal sizes, w/cm of 0.33 and 0.38, and three binder compositions: Type MS cement, Type HE cement with 30% of slag replacement, and Type HE cement with 20% of Class F fly ash. Comparisons and correlations among various test results used in evaluating the workability responses obtained for these mixtures are established. This is done to highlight advantages and limitations of the various test methods that can be used to assess workability of SCC designated for prestressed applications. Appropriate combinations of test methods that can be used to assess workability of SCC at the precast plant are recommended, and ranges of acceptance of the various test methods are established.


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