• Title/Summary/Keyword: Amorphous steel fibers

Search Result 20, Processing Time 0.029 seconds

Flexural Performance Characteristics of Amorphous Steel Fiber-Reinforced Concrete (비정질 강섬유보강콘크리트의 휨성능 특성)

  • Ku, Dong-Oh;Kim, Seon-Du;Kim, Hee-Seung;Choi, Kyoung-Kyu
    • Journal of the Korea Concrete Institute
    • /
    • v.26 no.4
    • /
    • pp.483-489
    • /
    • 2014
  • In this study, the flexural test of amorphous steel fiber-reinforced concrete was performed according to ASTM C 1609 to investigate its flexural performances. The amorphous steel fibers have different configurations from conventional steel fibers : thinner sections and coarser surfaces. Primary test parameters are fiber type (amorphous and conventional steel fibers), concrete compressive strength (27 and 50 MPa), and fiber volume fraction (0.25, 0.50, and 0.75%). Based on the test results, flexural strength and flexural toughness of the amorphous and conventional steel fiber-reinforced concrete were investigated. The results showed that the addition of the amorphous steel fibers into concrete could enhance both flexural strength and toughness while the addition of the conventional steel fibers into concrete was mainly effective to increase the flexural toughness.

An Experimental Study of Shear Capacity for One-way Concrete Slabs Reinforced with Amorphous Micro Steel Fibers (비정질 강섬유 보강 일방향 콘크리트 슬래브의 전단성능에 대한 실험적 연구)

  • Kim, Seon-Du;Choi, Kyoung-Kyu;Choi, Oan-Chul;Choi, Se-Jin
    • Journal of the Korean Recycled Construction Resources Institute
    • /
    • v.1 no.2
    • /
    • pp.128-135
    • /
    • 2013
  • In this study, one-way shear tests were performed to investigate the shear capacity of amorphous steel fiber-reinforced concrete slabs. Primary test parameters were the shear reinforcing method(Stirrups or amorphous steel fibers) and shear reinforcement ratio(0.25 and 0.5%). A series of four one-way slab specimens including a specimen without shear reinforcement and three specimens with shear reinforcements(stirrup, 0.25%, and 0.5% amorphous steel fibers) were tested. The test results showed that 0.25% amorphous steel fibers improved the shear capacity, but 0.5% amorphous steel fibers did not improve the shear capacity compared to the specimen with conventional shear reinforcement of 0.25%. Additional study is needed to understand the variation of shear capacity according to fiber volume fraction.

Effect of Amorphous Steel Fiber on the Spalling Characteristics of High-strength Concrete (고강도콘크리트의 폭렬특성에 미치는 비정질 강섬유의 영향)

  • Kim, Jong-Ho;Kim, Gyu-Yong;Lee, Sang-Kyu;Hwang, Eui-Chul;Son, Min-Jae;Nam, Jeong-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2019.05a
    • /
    • pp.32-33
    • /
    • 2019
  • This study evaluated the effect of amorphous steel fibers on the spalling characteristics of high-strength concrete. with mix proportions of polypropylene (PP) fibers of 0.15% by concrete volume, and proportions of amorphous steel fibers of 0.3% and 0.5% by concrete volume. In the range of 0.3 vol% of amorphous steel fiber, the effect of suppression of the spalling and the prevention of degradation of strength was shown, but it was evaluated to be ineffective in the suppression of the spalling due to interferences in formation of pore network in the range of 0.5 vol.%.

  • PDF

Comparison Analysis of Fiber Distribution and Workability for Amorphous Steel Fiber Reinforced Concrete (비정질강섬유 보강콘크리트 작업성 및 섬유 분산성 비교분석)

  • Kim, Byoung-Il;Lee, Sea-Hyun
    • Resources Recycling
    • /
    • v.23 no.4
    • /
    • pp.47-57
    • /
    • 2014
  • The research was conducted to analyze workability and fiber distributions of amorphous steel fiber reinforced concrete by changing fiber length and fiber addition ratio. The inverted slump cone and vebe tests as well as slump test was performed to understand the fluidity of amorphous steel fibers which have quite different appearance compared to conventional steel fibers. Test results showed that thin plate type of amorphous steel fibers required different test approach to figure out workability since the reduction of workability from slump test was different that from inverted slump cone and vebe tests. In conclusion, fluidity of amorphous steel fibers to concrete was significantly degraded as fiber length and addition ratio increase. Also, fibers space in cement matrix was apparently reduced as the increase of fiber length and addition ratios without fiber balling.

Cracking Behavior of RC Tension Members Reinforced with Amorphous Steel Fibers (비정질 강섬유로 보강된 철근콘크리트 인장부재의 균열거동)

  • Park, Kyoung-Woo;Lee, Jun-Seok;Kim, Woo;Kim, Dae-Joong;Lee, Gi-Yeol
    • Journal of the Korea Concrete Institute
    • /
    • v.26 no.4
    • /
    • pp.475-482
    • /
    • 2014
  • This paper presents the experimental results concentrically reinforced concrete tension members and compares cracking behavior of amorphous steel fiber and normal steel fiber reinforced concrete members. Two kind of steel fibers were included as a major experimental parameter together with the six cover thickness to bar diameter ratio ($c/d_b$). The presence of amorphous steel fibers effectively controlled the splitting cracks initation and propagation. In the amorphous steel fiber reinforced specimens, no splitting cracks were observed that becomes higher with cover thickness to bar diameter ratio is 2.0. Crack spacing of the each specimens reinforced with amorphous steel fibers and normal steel fibers becomes larger with the increase in cover thickness, and also measured maximum and average crack spacing are significantly smaller than current design code provision. Based on the measured crack spacings, a relationships for predicting the crack spacing is proposed using the measured average crack spacing in amorphous steel fiber reinforced concrete tension members.

Thermal performance prediction of amorphous steel fibers mixed into the floor heating system (비정질 강섬유 혼입 바닥난방시스템의 열성능 평가)

  • Cho, Hyun;Pang, Seung-Ki
    • Journal of Energy Engineering
    • /
    • v.25 no.3
    • /
    • pp.130-135
    • /
    • 2016
  • The thermal performance of amorphous steel fibers mixed floor heating system was evaluated. Analysis of results, depending on the hot water supply temperature changes, the average temperature of the bottom of the hot water supply temperature is an amorphous steel fiber floor heating system is about 2~4% higher. The average temperature of the floor surface to 1.5m air amorphous steel fiber system is 1~2% higher. The amount of heat supplied to indoor air (1.5m) from the bottom surface of amorphous steel fiber floor heating system is about 7~8% higher

Effects of Mixing Fiber Types on Electromagnetic Wave Shielding Effectiveness of Mortar (혼입섬유에 따른 모르타르의 전자파 차폐 효과)

  • Kim, Young-Jun;Yi, Chongku
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2015.05a
    • /
    • pp.150-151
    • /
    • 2015
  • In this study, the electromagnetic shielding performance of mortar with different metal fiber, as part of the development of a electromagnetic shielding construction material, was measured according to KS C 0304. The results showed that the amorphous steel fibers can shield electromagnetic effectively than the oter conventional steel fibers. The superior performance of the amorphous steel fiber may be attributed its plate shape geometry.

  • PDF

Comparsions for Flexural Performance of Amorphous Steel Fiber Reinforced Concrete (비정질강섬유보강콘크리트의 휨성능 비교분석)

  • Kim, Byoung-Il;Lee, Sea-Hyun
    • Resources Recycling
    • /
    • v.24 no.3
    • /
    • pp.66-75
    • /
    • 2015
  • The flexural performance of amorphous steel fibers having environmental and economy benefits due to relatively short manufacturing process were evaluated as well as that of hooked steel fibers by varing fiber length and volume fraction. Fiber lengths were 10 mm, 20 mm, 30 mm and fiber volume fractions were varied from 0.3% to 1.2%. Test results with flexural performance showed that mixing design needs to be careful because of relatively high volume of amorphous steel fiber compared to hooked steel fibers. High flexural strength was obtained from both longer fiber length and higher volume fraction. Residual strength and toughness of amorphous steel fiber were similar to that of hooked steel fiber, even though rapid dropping of applied load right after concrete matrix breaking. It can be judged that relatively high ability of energy dissipation around first cracking area relatively overcome rapid dropping of loading.

Investigation on the Applicability of Structures by Evaluating the Static Properties and the Impact Resistance Performance of Amorphous Metallic Fiber Reinforced Cement Composites (비정질 강섬유보강 시멘트복합체의 정역학특성 및 내충격성능 평가를 통한 구조물 적용 가능성 검토)

  • Kang, Il-Soo;Kim, Gyu-Yong;Lee, Bo-Kyeong;Lee, Sang-Kyu;Son, Min-Jae;Nam, Jeong-Soo
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2017.11a
    • /
    • pp.79-80
    • /
    • 2017
  • This study examined the effect that the amorphous metallic fibers had on the static mechanical properties and the impact resistance of cement composites to those of hooked steel fibers. The hooked steel fiber exhibited pull-out from the matrix after the peak flexural stress was attained, while the amorphous metallic fiber was not pulled out from the matrix, but was instead cut off. In terms of impact resistance, the amorphous metallic fiber reinforced cement composite was found to be more effective at resisting cracking than the hooked steel fiber reinforced cement composite. Therefore, amorphous metallic fiber should be used in fiber reinforced cement composite materials, and for structural materials, and for protection panels.

  • PDF

Compressive Properties of Amorphous Metal Fiber Reinforced Concrete Exposed to high Temperature

  • Lee, Jun-Cheol;Kim, Wha-Jung;Lee, Chang-Joon
    • Journal of the Korea Institute of Building Construction
    • /
    • v.12 no.2
    • /
    • pp.183-193
    • /
    • 2012
  • Compressive property of high strength concrete with amorphous metal fibers subject to high temperature has been investigated. The measure of this investigation includes explosive spalling, weight loss, residual compressive strength, strain at peak stress, elastic modulus, and residual energy absorption capacity after exposure to $400^{\circ}C$, $600^{\circ}C$and $800^{\circ}C$. In addition to the amorphous metal fiber, two other types of fibers (polypropylene fiber and hooked-end steel fiber) were also included in this investigation for comparison. The experimental program was conducted with high strength concrete using several combinations of the fiber types. The testing result shows that the concrete with amorphous metal fibers plus polypropylene fibers shows a superior behavior than those using other combination or single fiber type ingredient.