• International Journal of Concrete Structures and Materials
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• v.7 no.1
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• pp.51-59
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• 2013

The use of light-gauge steel framing in low-rise commercial and industrial building construction has experienced a significant increase in recent years. In such construction, the wall framing is an assembly of cold-formed steel (CFS) studs held between top and bottom CFS tracks. Current construction methods utilize heavy hot-rolled steel sections, such as steel angles or hollow structural section tubes, to transfer the load from the end seats of the floor joist and/or from the load-bearing wall studs of the stories above to the supporting load-bearing wall below. The use of hot rolled steel elements results in significant increase in construction cost and time. Such heavy steel elements would be unnecessary if the concrete slab thickening on top of the CFS wall can be made to act compositely with the CFS track. Composite action can be achieved by attaching stand-off screws to the track and encapsulating the screw shank in the deck concrete. A series of experimental studies were performed on full-scale test specimens representing concrete/CFS flexural elements under gravity loads. The studies were designed to investigate the structural performance of concrete/CFS simple beams and concrete/CFS continuous headers. The results indicate that concrete/CFS composite flexural elements are feasible and their structural behavior can be modeled with reasonable accuracy.

• Journal of Korean Society of Steel Construction
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• v.14 no.5 s.60
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• pp.665-674
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• 2002

The back-to-back and box-shaped headers used in light gauge steel structures have some disadvantages, i.e., construction efficiency and cost competitiveness. As such, cold-formed steel L-shaped headers have been developed and are used actively in advanced nations. However, this system has not been used in Korea because of inadequate investigation and adaptation efforts and lack of application example. Thus, this research evaluated the structural performance of L-header using buckling analyses and bending tests. Test results were compared using the AISI design criteria. Test results showed that local buckling and distortional buckling governed buckling behavior in gravity loads and uplift loads, respectively. These results were consistent with the calculated nomial strengths using the AISI design criteria.

• Fire Science and Engineering
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• v.24 no.6
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• pp.89-97
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• 2010

In recent fire protection system, the pipings should be light weighted, seismic proof and wrought with non-welding method. The light weighted stainless steel pipes and fittings, satisfying these requirements, are already used as a fire protection system in Germany, Netherland, Taiwan, Australia, United States and Japan. Accordingly, performance evaluation tests were carried out to determine whether or not the fittings can be used in the pipings. As the performance evaluation tests, we conducted vibration test, water hammering test, bending test and fire test. With the results of the tests, we concluded that the fittings can be used in the fire protection system, and that the life expectancy of the fittings exceeds that of buildings.

• Magazine of the Korean Society of Agricultural Engineers
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• v.41 no.4
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• pp.66-76
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• 1999

In this study , the optimum structural components for the rural house design using the light gauge cold-formed steel frame is proposed. The proposed components were optimzed by the developed model composed with the analysis model and LGC database. The analysis model adapts FEA(finite element analysis). LGC database and calculation of element force adapt the design criteria of KISC. The structure of house is divided into header, bearing wall and foof truss. The variable of the each structure of house are defined component which designed by the case of load, aize and space. The designed weight were used for optimization procedure of the divided components.

• Fire Science and Engineering
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• v.24 no.5
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• pp.94-101
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• 2010

The pipes using in water-based fire protection systems are used steel pipes for ordinary piping, carbon steel pipes for pressure service, copper and copper alloy seamless pipes and tubes, etc. By last buildings of high-rising, complexity, in fire protection systems, the corrosion resistance, easy construction, lightweight and cost-effective use of the pipes is being considered. Among the pipes, the possibility of used for fire protection system being used in the existing copper pipe of material properties, strength, corrosion resistance, heat resistance through and compare the performance was evaluated. As a result of that assessment light gauge stainless steel pipes for ordinary piping (KS D 3595) at a water pressure of less than 1.2 MPa can be used in sufficient physical properties, strength, corrosion resistance, heat resistance and have been observed.

• Steel and Composite Structures
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• v.19 no.6
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• pp.1599-1610
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• 2015

Cold Formed Steel members are widely used in today's construction industry. However the structural behavior of light gauge high strength cold formed steel sections characterized by various buckling modes are not yet fully understood. Because of their simple forming and easy connections, the commonly used cold formed sections for beams are C and Z. However both these sections suffer from certain buckling modes. To achieve much improved structural performance of cold formed sections for beams both in terms of strength and stiffness, it is important to either delay or completely eliminate their various modes of buckling. This paper presents various innovative sectional profiles and stiffening arrangements for cold formed steel beams which would successfully contribute in delaying or eliminating various modes of premature buckling, thus considerably improving the load carrying capacity as well as stiffness characteristics of such innovative cold formed sections compared to conventional cold formed steel sections commonly used for beams.

• Steel and Composite Structures
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• v.7 no.1
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• pp.35-52
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• 2007

The cold formed light-gauge profiled steel sheeting can offer considerable shear resistance acting in the steel building frame. This paper conducted the full-scale test on the shear behavior of stressed skin diaphragm using profiled sheeting connected by the self-tapping screws. A three-dimensional finite element model that simulates the stressed skin diaphragm was developed. The sheet was modeled using thin element model while the supporting members were simulated using beam elements. Fasteners were represented in the numerical model as equivalent springs. A joint test program was conducted to characterize the properties of these springs and results were reported in this study. Finite element model of the full-scale test was analyzed by use of the ANSYS package, considering nonlinearity caused by the large deflection and slip of fasteners. The experimental data was compared with the results acquired by the EUR formulas and finite element analysis.

• Steel and Composite Structures
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• v.9 no.3
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• pp.255-274
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• 2009

This paper presents an experimental study of a newly developed composite floor system, built up from thin-walled C-profiles and upper concrete deck. Trapezoidal sheeting provides the formwork and the fastening of the sheet transmits the shear forces between the C-profiles and the deck. The modified formation of the standard self-drilling screw in the beam-to-sheet connection is applied as shear connector. Push-out tests are completed to study the composite behaviour of the different connection arrangements. On the basis of the test results the behaviour is characterized by the observed failure modes. The design values of the connection stiffness and strength are calculated by the recommendation of Eurocode 4. In the next phase of the experimental study six full-scale composite beams are tested. The global geometry is based on the proposed geometry of the developed floor system. The applied shear connections are selected as the most efficient arrangements obtained from the push-out tests. The experimental behaviour of the composite beams are discussed and evaluated. As a conclusion of the experimental study the Eurocode 4 plastic design method is validated for the developed composite floor.

• Journal of Korean Society of Steel Construction
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• v.16 no.4 s.71
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• pp.397-406
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• 2004

This paper presents the test and evaluation results on the shear strength and stiffness of a light steel stud wall from a lightweight foamed mortar (lightweight hybrid wall). The use of a lightweight foamed mortar was aimed at improving structural performance, thermal performance, and finish. Studiesshowed that it did not affect thermal performance, but it contributed to structural performance and finish when the unit weight was more than 0.8 (Editor's note: Please indicate the unit of measurement.). In this study, 14 specimens-whose parameters included the specific gravity of the lightweight foamed mortar (0.6, 0.8, 1.0, 1.2), the spacing of the stud (450 mm, 600 mm, or 900 mm), finishing materials (such as lightweight foamed mortar, OSB, and gypsum board), and bracing-were manufactured. Three typical, steel house-framing specimens were added to compare the test results with the 14 specimens. The results of in-plane shear tests show that the use of lightweight foamed mortar (1.15~5.38 times stronger, 1.45~13.7 times stiffer) results in ultimate strength and initial stiffness. In addition, it was possible to widen the stud spacing to up to 900 mm without decreasing shear strength. It was very important to prevent the lightweight foamed mortar from shrinking and to secure the adhesion between the steel stud and the lightweight foamed mortar to improve structural performance.

• 한국태양에너지학회:학술대회논문집
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• 2009.11a
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• pp.236-240
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• 2009

Dry wall using steel stud has the advantage of possibility to install various building, so it used to many buildings inside and outside of the country very rapidly. Though Light gauge steel framed housing offers many advantages to the consumer and the builder, the use of steel studs in wall system cause thermal problems such as thermal performance and pattern staing on walls. The present study has been conducted to observe effect of stud by the shape, and two kind of stud is made for this test to compare thermal performance. The test was conducted by setting those stud on the chamber and heating them. As the results of test and photograping by using TVS, there was temperature gap of each stud, and surface temperature of each section was appeared differently due to shape of stud delaying thermal bridge.