• Proceedings of the Korean Fiber Society Conference
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• 1996.10a
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• pp.539-544
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• 1996

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.100-101
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• 2017

LEFC(Light Emotion Friendly Conceret) was developed in Korea with demands of esthentic requirements in line with the recent developmental trend of concrete technology. The LEFC is made by inserting transparent transparent rods, and this forms a heterogeneous structure in the concrete matrix causing the LEFC substrate to crack due low adhesion between the rod and the cement. In this study, as a way to strengthen the bonding to the rod inserted in the LEFC, high strength vinylon fibers of varying mixture ratios were applied and physical properties were tested accordingly. To study the effect of different spacing of the bars on the LEFC, physical property testing was conducted on respective specimens with two different diameters (5mm, 10mm) inserted in different intervals of spacing (10mm, 15mm, and 20mm).

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.3
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• pp.314-320
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• 2022

The function of reinforcing fibers used in building materials is to maintain resistance to bending loads and to function for cracking caused by drying shrinkage. High-density fiber-cement composites are mainly used for linear plates and are used to increase bending resistance. Therefore, tensile properties, bonding strength with cement hydrate, alkali resistance, and the like are required. Recently, as the non-combustible performance has been strengthened, a function to minimize the occurrence of sparks during high-temperature heating has been added. Therefore, the use of organic fibers is limited. In this study, a study was conducted to replace polypropylene used as reinforcing fiber with hemp fiber with excellent heat resistance. Hemp fibers have excellent heat resistance, good affinity with cement, and excellent alkali resistance. Based on the total volume of polypropylene fibers used in the existing formulation, the non-combustible performance was compared and evaluated by using hemp fibers instead of the polypropylene fibers, and basic physical properties such as flexural strength were tested. As a result of conducting a non-combustibility and physical property test using hemp fibers with a fiber length of 7 mm using 2 % and 3 % by weight, it was found that there is no remaining time of the flame, and the flexural strength can be secured at 95 % level of the existing polypropylene fiber.

• Journal of the Korea Institute of Building Construction
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• v.14 no.6
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• pp.639-645
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• 2014

For the construction materials, concrete, as the most widely used material, is focused on its improvement of performance. Although concrete has many advantages of easiness of handling, economical benefits, and high compressive strength, low tensile strength, brittleness and drying shrinkage are reported as the drawbacks of concrete. Hence, to solve these drawbacks of concrete, many research has conducted especially using fiber-reinforced concrete technology. Especially, HPFRCC which has high volume of fiber reinforcement was suggested as a solution of these drawbacks of normal concrete with increased ductility while it has the possibility of workability loss with fiber clumping which can cause low performance of concrete. Therefore, in this paper, optimized fiber combination with either or both metal and organic fibers is suggested to provide better performance of HPFRCC in tensile strength and ductility. As the results of experiment, better workability was achieved with 1 % of single fiber rather than multiple fibers combinations, espeically, short steel fiber showed the best workability result. Furthermore, in the case of organic fibers which showed higher air content than steel fibers, higher compressive strength was achieved while lower tensile and flexural strength were shown.