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Showing 1 to 14 of 14 for “"Polypropylene fibers"”.
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Phase separation spinning of polypropylene fibers
Polypropylene fibers were spun from solutions of different polymer contents undergoing phase separation. The range of concentrations used was 25 to 60 wt. % polypropylene. The solvent used was naphthalene. After the naphthalene was extracted from the fibers using diethyl ether the fiber's …
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Increasing residual structural capacity of cracked concrete railroad crossties with polypropylene fibers
The purpose of this research was to employ polypropylene fibers into concrete railroad crossties to increase its residual structural capacity once the concrete has cracked. The center negative flexural cracking is considered as a serious failure mode in concrete railroad crossties, which decreases …
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Properties and characteristics of polypropylene fibers spun by the phase-separation technique
… technique as applied to the production of polypropylene fibers from naphthalene solutions. The solutions were spun through a single 2.00 millimeter spinneret at compositions of 15 and 22 per cent polymer and at temperatures of 145 and 160°C. Linear velocities in the spinneret and draw …
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Geotechnical performance using alkaline activated fly ash for soil mixtures with and without polypropylene fibers
… was added to a mix of fly ash class F and polypropylene fibers to stabilize and reinforce Kaolin clay (S1) and marine clay (S2) respectively. The fly ash solid ratio was considered to be 10%, 20%, 30%, 40%, while polypropylene fiber proportions adapted for the study were 0.5%, 0.75%, 1% …
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Residual Strength of Ultra-High Performance Concrete After Exposure to Elevated Temperatures
… by the manufacturer incorporates only steel-fibers to improve the tensile properties of the concrete. The enhanced mixture, which is of primary focus in the study, incorporates additional polypropylene fibers to improve the fire-resistance behavior. Specimens from each mixture were cast into …
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Oil sorption behavior of fibrous substrates
… are a hazard to the environment. Synthetic fibers like polypropylene occupy a major share of the oil spill cleanup industry. Being non-biodegradable, the oil soaked synthetic sorbents pose a risk to the environment when they are disposed. Furthermore, if the oil soaked polypropylene sorbents …
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Steel-free hybrid reinforcement system for reinforced concrete flexural members
… (FRP) rebars and discrete randomly distributed polypropylene fibers. This hybrid system may eliminate problems related to corrosion of steel reinforcement while providing requisite strength, stiffness, and desired ductility, which are shortcomings of FRP reinforcement system in reinforced …
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IMPROVEMENT OF DYNAMIC PROPERTIES AND SEISMIC RESPONSE OF CLAY USING FIBER REINFORCEMENT
… inclusion of randomly distributed short virgin polypropylene fibers (C3H6) in clay has proven to significantly improve the static geotechnical properties of clay such as shear, compression, tensile strengths, and so on. These improvements have triggered great interest in the possibility of …
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Polypropylene fiber reinforced concrete in railway crossties
… under tensile stresses. Inclusion of synthetic polypropylene macro fibers in concrete is known to improve crack resistance and is a feasible solution for prolonging the life of crossties. The present study investigated the performance of synthetic polypropylene macro fiber reinforced concrete …
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Development, application and early-age monitoring of fiber-reinforced ‘crack-free’ cement-based overlays
… Fiber types included different sizes of polypropylene and cellulose fibers and one type of glass fiber (volume fraction ranging between 0-0.4%). Glass fibers at a small dosage of 0.1% were the most efficient fiber and completely eliminated cracking. Of the two field projects considered: …
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Response of high strength concrete columns under fire-induced biaxial bending
… of one NSC, three HSC and two HSC columns with polypropylene fiber, and were tested under a standard and two design fires. Results from the tests show that HSC columns exhibit lower fire resistance due to occurrence of spalling and faster degradation of strength. But these HSC columns can …
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Mechanical behavior of nonwoven felts
… materials manufactured from a set of disordered fibers consolidated by bonds of different nature depending on the particular material or processing technique. The industrial applications of these materials have grown very rapidly in recent years with the incorporation of new fibers and …