• International Journal of Concrete Structures and Materials
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• 제2권1호
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• pp.35-39
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• 2008

This experimental study examines the applicability of polymer mortar permanent forms using a methyl methacrylate (MMA) solution of waste expanded polystyrene (EPS) to develop effective recycling processes for the EPS, referring to the flexural behavior of a polymer-impregnated mortar permanent form with almost the same performance as commercial products. An MMA solution of EPS is prepared by dissolving EPS in MMA, and unreinforced and steel fiber-reinforced polymer mortars are mixed using the EPS-MMA-based solution as a liquid resin or binder. Polymer mortar permanent forms (PMPFs) using the EPS-MMA-based polymer mortars without and with steel fiber and crimped wire cloth reinforcements and steel fiber-reinforced polymer-impregnated mortar permanent form (PIMPF) are prepared on trial, and tested for flexural behavior under four-point (third-point) loading. The EPS-MMAbased PMPFs are more ductile than the PIMPF, and have a high load-bearing capacity. Consequently, they can replace PIMPF in practical applications.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.367-370
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• 2003

Lightweight polymer concrete with steel fiber can be used for thin panel, high building and large span structures due to its may advantages such as its durability, low weight, control of crack propagation, high strength and toughness. This study experimented about steel fiber reinforcement of lightweight polymer concrete using synthetic lightweight aggregate. The test result shows that the maximum strain and elastic modulus are in the range of $0.012{\sim}0.014\;and\;50.2{\times}10^3{\sim}51.0{\times}10^3kgf/cm^2$, respectively. The flexural load-deflection curves after maximum load are shown in smoothly with increase of steel fiber content

• 한국강구조학회 논문집
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• 제26권2호
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• pp.69-79
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• 2014

본 연구에서는 콘크리트 섬유보강플라스틱(FRP)로 보강된 철골보의 정적 휨하중상태에서 휨거동에 관한 실험결과를 제시하였다. 아라미드섬유 스트립과 탄소섬유 스트립으로 보강된 4개의 실험체를 제작하였으며, 1개의 기준실험체를 제작하였다. 이중 두 실험체는 부분보강방식으로 보강되었다. H빔은 두 종류의 파괴모드를 가지고 있는데, (1) 부분보강 실험체에서는 FRP 스트립이 탈락(debonding)되는 파괴모드를 보이고 있으며, 전면보강 실험체에서는 FRP 스트립이 파단(rupture)되는 거동을 보이고 있다. 실험결과 16%의 휨내력 상승효과를 관찰하였다.

• 한국공간구조학회논문집
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• 제3권3호
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• pp.85-93
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• 2003

Steel, concrete and their combination materials are the most 6commonly used materials for civil engineering structural systems such as buildings, bridge structures and other structures. Recently, however, fiber reinforced polymer (FRP) composites, a relatively new composite material made of fibers and polymer resins, have been gradually used in structural systems as an alternative structural material. This paper describes a comparison of design strength equations for steel column and FRP composite column based on design philosophies. The safety factors used in allowable stress design (ASD) are relatively higher in FRP structural design than steel structural design. Column critical stress equations of FRP composites column from an experimental study can be represented by Euler elastic buckling equation at the long-range of slenderness, and an exponential form at the short-range of slenderness as defined in Load and Resistance Factor Design (LRFD) of steel column. The column strength of steel and FRP composite columns in large slenderness is independent of material strength, this result verified the elastic buckling equation as derived by Eq. (15) and Eq. (5).

• Steel and Composite Structures
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• 제45권5호
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• pp.653-663
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• 2022

This study reports the results of a series of tests of pultruded glass fiber reinforced polymer (P-GFRP) box section composite profile columns, geometrically similar with/without concrete core, containing 0-1-2-3% steel fiber, with different lengths. The recycled steel wires were obtained from waste tyres. The effects of steel fiber ratio on the collapse and size effect of concrete filled P-GFRP columns under axial pressure were investigated experimentally and analytically. A total of 36 columns were tested under compression. The presence of pultruded profile and steel wire ratio were selected as the primary variable. The capacity of pultruded profiles with infilled concrete are averagely 9.3 times higher than the capacity of concrete without pultruded profile. The capacity of pultruded profiles with infilled concrete are averagely 34% higher than that of the pultruded profiles without infilled concrete. The effects of steel wire ratio are more pronounced in slender columns which exhibit buckling behavior. Moreover, the proposed analytical approach to calculate the capacity of P-GFRP columns successfully predicted the experimental findings in terms of both pure axial and buckling capacity.

• Steel and Composite Structures
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• 제18권1호
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• pp.51-69
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• 2015

In recent years, the use of fiber reinforced polymer composites has increased because of their unique features. They have been used widely in the aircraft and space industries, medical and sporting goods and automotive industries. Thanks to their beneficial and various advantages over traditional materials such as high strength, high rigidity, low weight, corrosion resistance, low maintenance cost, aesthetic appearance and easy demountable or moveable construction. In this paper, it is aimed to determine and compare the geometrically nonlinear static and dynamic analysis results of footbridges using steel and glass fiber reinforced polymer composite (GFRP) materials. For this purpose, Halgavor suspension footbridge is selected as numerical examples. The analyses are performed using three identical footbridges, first constructed from steel, second built only with GFRP material and third made of steel- GFRP material, under static and dynamic loadings using finite element method. In the finite element modeling and analyses, SAP2000 program is used. Geometric nonlinearities are taken into consideration in the analysis using P-Delta criterion. The numerical results have indicated that the responses of the three bridges are different and that the response values obtained for the GFRP composite bridge are quite less compared to the steel bridge. It is understood that GFRP material is more useful than the steel for the footbridges.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1993년도 가을 학술발표회 논문집
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• pp.213-219
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• 1993

The box girder was developed using polymer concrete, box girder were made for flexural behavior evaluation. The box girder was reinforced with reinforcing steel bars and fiber glass roving cloths. Failure loads were 13.5 tons and 16.6tons for steel reinforced girder and fiber glass reinforced girder, respectively. Especially for the fiber glass reinforced girder, the shape was not changed even after failure. It is expected that application of this idea will be useful for developing under ground box, girder, utility tunnel, small stream bridge box, etc.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1995년도 가을 학술발표회 논문집
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• pp.171-177
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• 1995

Fracture mechanics does work for concrete, provided that one uses a proper, nonlinear form of fracture mechanics in which a finite nonlinear zone at fracture front is being considered. The fracture process zone is a region ahead of a traction-free crack, and the development of model of fracture process zone is most important to describe fracture phenomena in concrete. This paper is about fracture behavior of concrete cylinder under lateral pressure. Concrete cylinders were made of high strength normal connote, steel fiber reinforced concrete and steel fiber reinforced polymer-impregnated concrete and concrete and the fracture behavior such as cracking propagation and ultimate load are observed. The fracture process zone is modelled by a Dugdale-Barenblatt type model with linear tension-softening curve and are implemented to the boundary element technique for the fracture analyses of the cylinders. The experimental results are compared with analysis results and tension-softening curves for the steel fiber reinforced concrete and steel fiber reinforced polymer-impregnated concrete are obtained by back analyses.

• 한국구조물진단유지관리공학회 논문집
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• 제6권2호
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• pp.135-143
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• 2002

This study is to investigate its use by applying stainless steel wire mash reinforcement method of construction, which is newly developed, on the high strength concrete beam mixed with polymer-steel fiber. In this test, it is investigated and observed such as follows: the ultimate load, the initial flexure crack load, the initial diagonal tension crack load, the relation between load and deflection, load-strain relation, and also crack growth and fracture aspect by increasing load. The results of this test are; first, the stainless steel wire showed some useful reinforcement effects in multiplying the steel's resisting force of moment to the tensile force of beam or slab: second, the promoting strength and internal force was made in the process of the integration at the same reaction by using the penetrating polymer-mortar with an excellent durability and physical property. On the basis of this results, because such instances in applying stainless steel wire Mash reinforcement method of construction have been few so far, through the experimental investigation such as this test over and over again, the efficient and useful method must be developed for the practice.

• Structural Engineering and Mechanics
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• 제63권5호
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• pp.629-637
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• 2017

Continuous concrete beams are commonly used as structural members in the reinforced concrete constructions. The use of fiber reinforced polymer (FRP) bars provide attractive solutions for these structures particularly for gaining corrosion resistance. This paper presents experimental results of eight two-span continuous concrete beams; two of them reinforced with pure glass fiber reinforced polymer (GFRP) bars and six of them reinforced with combinations of GFRP and steel bars. The continuous beams were tested under monotonically applied loading condition. The experimental load-deflection behavior and failure mode of the continuous beams were examined. In addition, the continuous beams were analyzed with a numerical method to predict the load-deflection curves and to compare them with the experimental results. Results show that there is a good agreement between the experimental and the theoretical load-deflection curves of continuous beams reinforced with pure GFRP bars and combinations of GFRP and steel bars.