Effect Of Polypropylene Fibers Research Articles

Effect of Polypropylene Fibres on Flexural Strength of M30 Grade Concrete

Concrete made with Portland cement has strong compressive strength but it has weak tensile strength and it tends to be brittle. Also cracks start to develop as soon as concrete is placed and before it has properly hardened which may lead to weakening of concrete structures, fracture and failure and general lack of durability. Thus this research is aimed at reducing the aforementioned shortcomings of concrete to increase its applicability and performance. The tensile strength of concrete could be enhanced by using conventional rod reinforcements and to a certain extent by the inclusion of a sufficient volume of fiber. Addition of fibers also leads to a reduction in shrinkage cracking. We have used steel fibers as reinforcements and Polypropylene as the fiber.

ANALYSIS OF THE EFFECTIVENESS OF POLYPROPYLENE FIBERS USAGE AS SORBENTS OF OIL SPILLS RESULTING FROM THE TRANSPORT ACCIDE / POLIPROPILENO PLUOŠTO NAUDOJIMO EFEKTYVUMAS IŠSILIEJUS NAFTAI TRANSPORTO OBJEKTUOSE

The effectiveness of polypropylene fibers as sorbents of oil-water emulsions was the object of the research in the present publication. Thus the sorption capacity of the synthetic material of the regional production with for emulsions of different concentration was investigated. Santrauka Straipsnyje nagrinėjama polipropileno pluošto naudojimo avarinionaftos išsiliejimo metu problema. Polipropileno pluoštasnaudojamas kaip naftą sugerianti medžiaga. Pateiktos skirtingostorio polipropileno pluošto išsiliejusios naftos sugeriamumosavybės.

Study on the Dynamic Performance of Polypropylene Fiber Reinforced Concrete

The dynamic performance of polypropylene fiber reinforced concrete is studied with the SHPB experiment. The relationship of the strain-stress curves are all obtained in the experiment. The crack characteristics of polypropylene reinforced concrete and plain concrete are also investigated. Analyzed the relation between the character on the crack surface of concrete and material properties and the impact pressure. Also the multi-fractal characteristics are given on the crack surface of concrete. The crack distributions of plain concrete and polypropylene concrete are investigated. The crack resistance effects of polypropylene fiber are analyzed from the degree of closeness and uniformity.

The Mechanical Properties of Polypropylene Fiber Reinforced Polymer Modified Cement Mortar

Combining the effect of polypropylene fibers, such as the decrease of cement base material shrinkage and plastic crack, and the increase of material toughness, with the improvement of polymer on the interface between the fiber and matrix, both polypropylene fibers and polymer modifier were used in the cement mortar at the same time to make more excellent cement mortar materials. The improvement for cement mortar from different length of polypropylene fiber, polymer modifier (waterborne epoxy emulsion), mineral powder and silica ash were studied. Results showed that compared with the short fiber, the long fiber has a more obvious effect on the toughness, the best dosage of which is 0.6 kg/m3; the waterborne epoxy emulsion improved the bonding properties of interface between polypropylene fiber and cement mortar matrix, and then, long fibers improved flexural strength of cement mortar greatly, in terms of short fiber, effect is not manifest; With the increase of mineral powder, all the mechanical index of polypropylene fiber reinforced polymer modified cement mortar were improved and the effect of silica ash was better than that of mineral powder, the optimal replacement ratio were 0.1 and 0.3 respectively.

Properties Research and Mechanism Analysis of Polypropylene Fiber Reinforced FGD Gypsum Composites

Polypropylene fiber, stearic acid-polyvinyl alcohol emulsion and FGD gypsum were chosen to prepare fiber reinforced FGD gypsum composites by a certain process. The effects of polypropylene fiber and stearic acid-polyvinyl alcohol emulsion on the composites were observed, and their action mechanisms were also analyzed with physical molds of waterproofing mechanism established. QUANTA FEG 250 scanning electron microscope was used to observe the microcosmic morphology of the samples. The investigations indicated that the mechanical property of fiber reinforced FGD gypsum composites was enhanced by admixture with polypropylene fiber while the water-resistant property was improved by adding the organic emulsion which could make the strength loss induced.

Concrete spalling sensitivity versus microstructure: Preliminary results on the effect of polypropylene fibers

The phisyco-mechanical processes triggering concrete explosive spalling are related to the heat-induced micro- and meso-structural changes. To have new information on concrete properties at the microstructural level, as well as on how concrete spalling sensitivity is affected by polypropylene and steel fibers, and by aggregate type, ordinary and high-performance concretes are investigated in this research project, after being heated to different temperatures. The focus is on the relationship among porosity, vapor permeability, pore pressure and microcracking inside the cementitious matrix. Polypropylene fibers are shown to increase the total porosity, to favor microcracking and to reduce significantly pore pressure, to the advantage of concrete resistance to explosive spalling, whose risk is markedly reduced - or even zeroed.

Effect of Polypropylene Fibers on the Toughness of Concrete Materials

Effect of Polypropylene Fibers on the Toughness of Concrete Materials

Research on the Strength and Permeability of Fly Ash Concrete Mixing Fiber

The effect of polypropylene fiber and steel fiber on workability, strength and permeability of fly ash concrete was studied. Admixing polypropylene fiber or steel fiber in concrete, the workability of fresh concrete became worse. To Keep the same slump and well cohesiveness, mixing polypropylene fiber in concrete could not improve the early strength of concrete, steel fiber used in concrete can improve especially flexure strength obviously. The wear resistance of concrete with polypropylene fiber or steel fiber all increased, the permeability resistance was not decreased, impervious grade is still greater than W8.

Determination of the Optimal Polypropylene Fiber Addition to the Dense Bituminous Mixtures by the Aid of Mechanical and Optical Means

Polypropylene fibers are completely native modifiers and they do not have any dependence on abroad in case of technology. When viewed from this point, the modification of bituminous binders with polypropylene fibers is a very important step for our country’s “economical” concerns. In this study, first of all, the physical and chemical effects of polypropylene fibers on bitumen were investigated. Next, the amount of “optimum” polypropylene fibers that has to be added into the mixture was determined. In order to determine it, first, static creep tests and Marshall tests were carried out and then, images of the polypropylene fiber added bituminous binders under fluorescence microscopy were researched. With the application of physical and mechanical tests to the Marshall specimens prepared with the optimum polypropylene amount that was obtained, optimum bitumen content was determined and finally economical analyses were carried out. By carrying out extensive analyses it was seen that the utilisation of polypropylene fibers improves the physical and mechanical properties of the resultant asphalt mixture mainly by enhancing the permanent deformation resistance. On the other hand, polypropylene modification results in 30% economy from bitumen which is a clear indication of the benefit in the mass production of asphalt concrete.

Effect of polypropylene fibre on flexural properties of concrete composites containing fly ash and silica fume

The application of fly ash and silica fume in concrete composites by blending synchronously can improve the mechanical properties of concrete composites. However, the concrete composite becomes much brittle with the usage of fly ash and silica fume. Polypropylene fibre is often used to improve the ductility of concrete composites. This article discusses the effect of polypropylene fibre on the flexural properties of concrete composites containing fly ash and silica fume. Results reveal that the addition of polypropylene fibre can increase the flexural strength and decrease the flexural modulus of elasticity of the concrete composite containing fly ash and silica fume evidently. Furthermore, it is indicated that an increase in the fibre volume fraction leads to an increase in the flexural strength and a decrease in the flexural modulus of elasticity when the fibre volume fraction is not beyond 0.12 per cent. Polypropylene fibre seems to play an important role to improve the ductility of concrete composites containing fly ash and silica fume.

Effect of polypropylene fibers on thermogravimetric properties of self-compacting concrete at elevated temperatures

In this study, the effect of polypropylene (PP) fibers on thermogravimetric parameters of self-compacting concrete (SCC) containing indigenous materials was investigated experimentally and statistically. The mixes containing cement, water, fly ash, fine aggregate, coarse aggregate, and super plasticizer, with the addition of PP fibers (0%, 0.05%, 0.1%, and 0.15%) by volume of the mixtures, were prepared. The physical properties of SCC were determined at elevated temperatures (200, 400, and 600 °C) after cooling in the laboratory. Regression models were developed to determine the responses, and the optimum amount of 0.05% PP fibers by volume was measured. Copyright © 2012 John Wiley & Sons, Ltd.

Effect of polypropylene fibers on the uplift behavior of model footings embedded in sand

ABSTRACT: The kinematics of failure and the uplift response of plates embedded in sand and in fiber-reinforced sand layers at distinct embedment depths, when subjected to vertical pullout tests, are the main topics discussed in the present technical note. The uplift capacity of plates in sand backfill layers is increased by the insertion of 0.5% fibers in the backfilled material. The enhancement of the uplift capacity increases from about 70% for embedment depth/plate diameter ratio (H/D) equal to 1.0 to about 30% for H/D equal to 2.0, when compared with sand backfill at the same embedment. Distinct failure patterns were observed for plates embedded in sand and in fiber-reinforced sand backfills: intense radial cracking was observed for sand backfill, but only a few concentric fissures were seen for fiber-reinforced backfill, the former starting at tiny displacements and the latter appearing at large displacements. The fiber-reinforced sand layers demonstrated the ability to continue to increase strength with ongoing deformation, suggesting a very ductile material.

Study on Freeze-Thaw Performance of Polypropylene Fiber Reinforced Cement-Stabilized Aggregate

In this paper, the authors study the anti-freeze-thaw performance of a new type of semi-rigid base material named polypropylene fiber reinforced cement-stabilized aggregate, and freeze-thaw mass loss rate, freeze-thaw compressive strength, freeze-thaw splitting strength are used to evaluate the effect of polypropylene fiber on the anti-freeze-thaw performance, and the relationship of polypropylene fiber content, polypropylene fiber length with the anti-freeze-thaw performance are analyzed. The test after 10 freeze-thaw cycle shows that the mix of polypropylene fiber increase the freeze-thaw compressive strength and freeze-thaw splitting strength, and decrease the mass loss rate greatly. At the same time, the paper also determine the reasonable fiber content and fiber length, under this mix proportion, the mass loss rate reduce by 80%, the freeze-thaw compressive strength increase more than 12.1% and freeze-thaw splitting strength increase more than 13.4%. This research has laid an important foundation for the follow-up research and practice.

The effects of polypropylene fibers on the properties of reinforced concrete structures

In this study, the results of polypropylene fibers reinforced concrete properties have been presented. The compressive strength, permeability and electric resistivity of concrete samples were studied. The concrete samples were made with different fibers amounts from 0 to 2 kg m −3. Also, the samples fabricated with coral aggregate and siliceous aggregate were examined and compared. The samples with added polypropylene fibers of 1.5 kg m −3 showed better results in comparison with the others. Moreover, coral aggregate concrete showed less electric resistivity and less compressive strength in comparison with samples fabricated of siliceous aggregates. It is concluded that the coral aggregates are not suitable for making concrete or using in concrete structures in the onshore atmosphere.

Effect of Polypropylene Fiber on Mechanical Properties of Concrete Containing Fly Ash

A designed experimental study has been conducted to investigate the effect of the fiber fraction of polypropylene fiber on the mechanical properties of concrete containing fly ash, a large number of experiments have been carried out in this study. The mechanical properties include compressive strength, splitting tensile strength and compressive modulus of elasticity. On the basis of the experimental results of the specimens of six sets of mix proportions, the mechanism of action of polypropylene fiber on these mechanical properties has been analyzed in details. The results indicate that there is a tendency of increase in the compressive strength and splitting tensile strength, and the modulus of elasticity of concrete containing fly ash decrease gradually with the increase of fiber volume fraction with appropriate content.

Effect of Polypropylene Fiber on Strength and Flexural Properties of Concrete Containing Silica Fume

A designed experimental study has been conducted to investigate the effect of polypropylene fiber on the compressive strength and flexural properties of concrete containing silica fume, a large number of experiments have been carried out in this study. The flexural properties include flexural strength and flexural modulus of elasticity. On the basis of the experimental results of the specimens of six sets of mix proportions, the mechanism of action of polypropylene fiber on compressive strength, flexural strength and flexural modulus of elasticity has been analyzed in details. The results indicate that there is a tendency of increase in the compressive strength and flexural strength, and the flexural modulus of elasticity of concrete containing silica fume decrease gradually with the increase of fiber volume fraction.

Effects of Polypropylene Fiber on Shrinkage of Masonry Cement Mortar

Experiments were carried out to investigate the dry-shrinkage of masonry mortar affected by mass content of polypropylene fiber. The results show that proper content of polypropylene fiber is helpful to effectively reduce dry-shrinkage of mortar especially in early age, the reduction relates to water to cement ratio of mortar. Meanwhile, the relationships of water to cement ratio and content of polypropylene fiber in affecting dry-shrinkage of masonry mortar are analyzed, which can be as reference for selecting such optimum values as water to cement ratio and content of polypropylene fiber in practices.

The spalling strength of ultra-fiber reinforced cement mortar

This is a research report about the effects of polypropylene fiber and wood fiber on mechanical properties of cement mortar. First, using advanced Hopkinson pressure bar (HPB) tests, it investigates the wave propagation in cement mortar comprised polypropylene fiber and wood fiber. Second, according to the experiment, the spallation position is recorded by high-speed camera. Thirdly, it analyzes the test data of ultra-fiber reinforced and common cement mortar by numerical method. Finally, it deduces the spalling strength of all kinds of cement mortar by integrating all experimental data above. The results indicate that, compared with the strength of common cement mortar, the dynamic spalling strength of ultra-fiber especially that of the polypropylene fiber reinforced cement mortar increases evidently. However, adding too much fibers will deteriorate the dynamic spalling strength of cement mortar specimen. So the results will provide a test basis for further optimizing performance of cement mortar.

Research about the Effect of Polypropylene Fiber on Mechanical Properties of Curing Sludge

In order to study the influence of modified polypropylene (PP) fiber on the physical and mechanical properties of curing sludge, the same amount of cement and different content of polypropylene fiber were mixed into the sludge. Unconfined compressive strength tests, water content tests and shear strength tests were carried out on different specimens with different curing time. The results show that the sludge curing effect is markedly improved by the addition of the polypropylene fiber. As to the curing sludge with the same curing time, when the content of the polypropylene fiber increases, the unconfined compressive strength and the cohesive strength greatly increase, and the internal frictional angle decreases.

Polypropylene Fiber Reinforced Concrete for Airfield Pavements:Modeling of Stress-Strain Curve Under Compression

An analytical model for compressive stress-strain curve of polypropylene fiber reinforced concrete (PPFRC) was proposed. The polypropylene fiber used was 60-mm long twisted fiber with aspect ratio of 120. The fiber was added in three volume fractions 0.2%, 0.4% and 0.6%. Tow concrete mixtures with varying water-cement ratio were used. The accuracy of the proposed model was evaluated by comparing the area under stress-strain curves for experimental and analytical model. The results showed good agreement between the experimental and analytical curves. In addition; empirical equations were proposed to quantify the effect of polypropylene fiber on compressive strength, strain at peak stress, and toughness of concrete in terms of fiber volume fraction.