• Journal of Korean Society of Steel Construction
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• v.25 no.2
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• pp.209-222
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• 2013

Eccentric axial loading test was performed for concrete-encased columns using 800MPa steel and 100MPa concrete. To maximize the contribution of the high-strength steel, L-shaped steel sections were placed at four corners, and connected to each other by lattices, links, or battens. Compared to a H-section of the same area, the moment-arm and strain of the L-sections are increased. Also, the corner L-sections provide good lateral confinement to concrete core. The test results showed that the peak strength and effective flexural stiffness of the L-section columns were increased by more than 1.4 times those of the H-section column.

• Journal of Industrial Technology
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• v.17
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• pp.213-218
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• 1997

This study is concerned with characteristics of bending collapse of aluminum members with multi-cell section. Aluminum is light so it is compatible of being used for vehicle structures members. Bending collpase behaviors of aluminum members with multi-cell section are very complex and tension failure mode are occured in experiment. In this paper, the aluminum members are modeled to be able to represent the tension failure mode and, characteristics of bending collapse of aluminum members with multi-cell section by experimental method are compared with the results of PAM-CRASH.

• Journal of Mechanical Science and Technology
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• v.18 no.6
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• pp.924-932
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• 2004

In this study, the axial collapse tests were performed under either static (or quasi-static) or impact loads with several collapse velocities based on the expectation that para-closed sections of the front-end side members (spot welded hat and double hat shaped section members) would show quite different collapse characteristics from those for seamless section. The test results showed that both of the hat and double hat shaped section members failed in the stable sequential collapse mode in the static or quasi-static collapse tests, while the double hat shaped section members underwent the unstable collapse mode especially when the impact velocity is high. The mean collapse loads in the hat shaped section members increase with collapse velocity for all the cases of the static, quasi-static, and impact collapse tests. In the double hat shaped section members, however, the mean collapse loads decrease with increase in collapse velocity in the impact tests.

• Proceedings of the KSR Conference
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• 2007.11a
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• pp.51-56
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• 2007

Pantograph of the electric train is the important part receiving current by adhereing contact wire. Wearing rate of pantograph or contact wire is changed by the type of pantograph and material of adhering part. In special, the weather influences the relative wearing rate and wearing type of pantograph Slider and Contact wire with steep wearing in arc and life cycle of pantograph slider. Presently, the weather causes side-wearing and over-wearing of pantograph slide installed in electric train. So it is difficult to manage and operate the electric train. Although the quality of slide using in line4 vehicle was finished the test in line 2 vehicle experimentally, it has to apply after pantograph is installed in some electric trains and check the influence in it and contact wire. It is because line4 section is very different from line2 section. Experimental application is the sequence to certify the safety and abrasion resistance importantly by enlarging experimental application with increase of the experimental electric train. The lenth of line4 in Seoul Metro is 71.5[km]. It is long section. The line is mixed DC 1,500[V] section and AC 25,000[V] section. It has underground section of 41.5[km] and ground section of 30[km]. Ground section is about 42% and receives much influence in the rain during the rainy season. After experimental application we found that this pantograph slide has twice as much abrasion resistance despite a little deviation and found the occurrence probability of arc and side-wearing is decreased considerably.

• Fire Science and Engineering
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• v.25 no.2
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• pp.80-87
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• 2011

On the result of load-bearing fire test to confirm the fire resistance of a composit beam, if the composit beam has lower fire resistance than required standard, it can be improved by section change. But if there are many types of section change, it takes much time and cost owing to conducting many tests. On this study, it was confirmed which part of the asymmetric H-section composit beam affected most on fire resistance by heat-transfer analysis. Then, we checked the tendency of improving fire resistance depend on section change by heat-transfer and non-linear structural analysis and suggested a changed section having 1-hour fire resistance.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.195-200
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• 2001

An experimental study on critical heat flux (CHF) has been performed for water flow in a uniformly heated vertical 3 by 3 rod bundle under low flow and a wide range of pressure conditions. The objective of this study is to investigate the parametric trends of CHF with 3 by 3 rod bundle test section where three unheated rods exist. The general trends of the CHF are coincident with previous understandings. At low flow and system pressure above 3 MPa, some critical qualities are larger than 1.0 due to counter-current flow in test sections. Since there is a supply of water to the heated section from unheated section, the maximum CHFs at system pressure between 2 and 4 MPa are not shown.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.3
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• pp.18-25
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• 1998

This paper performed stress analysis and bench test for the LOWER ARM of H' type which was improved on LOWER ARM with the section of H type. And we investigated the safety of the section of H' type. The results of this study are as follows ; The section of H' type satisfied the required safety factor and has the highest stress value on the B part of the LOWER ARM. And the magnitude is similar to the fatigue strength of the GCD45(300㎫). Hence, the H' type has an advantage to reduce the cost of production.

• Steel and Composite Structures
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• v.35 no.4
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• pp.495-508
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• 2020

Double skin composite walls are alternatives to concrete walls to resist gravity load in structures. The composite action between steel faceplates and concrete core largely depends on the internal mechanical connectors. This paper investigates the structural behavior of novel composite wall system with T section and under combined compressive force and bending moment. The truss connectors are used to bond the steel faceplates to concrete core. Four short specimens were designed and tested under eccentric compression. The influences of the thickness of steel faceplates, the truss spacing, and the thickness of web wall were discussed based on the test results. The N-M interaction curves by AISC 360, Eurocode 4, and CECS 159 were compared with the test data. It was found that AISC 360 provided the most reasonable predictions.

• Wind and Structures
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• v.7 no.1
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• pp.41-54
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• 2004

An analysis refinement of the Messina Strait suspension bridge project has been recently required, concerning mainly the yaw angle effects on the multi-box deck section aerodynamics and the vortex shedding at low reduced velocities $V^*$. In particular the possible interaction of the axial flow with the large cross beams has been investigated. An original test rig has been designed at this purpose allowing for both forced motion and free motion aero elastic tests, varying the average angle of attack ${\alpha}$ and the deck yaw angle ${\beta}$. The hydraulic driven test rig allowed for both dynamic and stationary tests so that both the stationary coefficients and the flutter derivatives have been evaluated for each yaw angle. Specific free motion tests, taking advantage from the aeroelastic features of the section model, allowed also the study of the vortex shedding induced phenomena.

• Proceedings of the Korean Geotechical Society Conference
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• 2001.06a
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• pp.45-54
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• 2001

In this study, slope stability analysis of LCRS(Leachate Collection Removel System) in waste landfill was peformed by large scale field test. Geocomat is new type of geocomposite product. Gecomat is a sort of Geocomposite product. It is composed of nonwoven geotextiles, woven geotextile, and geonet. Large scale field tests were performed on the slope of different two LCRSsections with static loading condition. One is LCRS section witch consist of GCL, HDPE and Geocomat, another is GCL, HDPE, and woven type geocomposite. The behavior of geosynthetics lined slope was monitored by incorporating instrumentation including vertical soil pressure meter, settlement plate, strain gauges, potential meter, displacement pin.. Based on the field monitoring, the Geocomat LCRS section is less sliding than the conventional geocomposite LCRS section.