• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.419-420
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• 2009

Recently, as development of industrialization and environment of concern, using of electric power is increased. So as a countermeasure, the construction of new nuclear power plant is increasing. This study is based on properties evaluation of power plant Structures Concrete. Then, We are going to use as a basic material.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.263-266
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• 2005

Recently, many researches for high-strength and high-durability concrete structure have remarkably been studied by adopting new construction material, fiber reinforced polymer (FRP). In connection with these research trend, the shearing capacity of concrete beams reinforced by GFRP stirrup which is developed in this study was evaluated. Experimental variables are span to depth ratio and spacing of shear reinforcement for test. In the result of test, the crack pattern, failure mode and shear load between shear steel reinforcement specimen and GFRP stirrup reinforcement specimen showed similar structural tendency. Therefore, it was investigated that the adaptability of shear-reinforced concrete structure with GFRP stirrup will be improved with further researches of shear design variables.

• International Journal of Concrete Structures and Materials
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• v.2 no.2
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• pp.107-113
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• 2008

The last 10 years have seen considerable growth in the use of proprietary and special repair cements for concrete pavements in the state of Oklahoma. Many of these products lend themselves to "fast track" construction techniques that allow reopening to traffic within 12 hours or less. These products achieve high early strengths by accelerating the Portland cement hydration process for both Type I and Type III cements. In this paper, the important features of a durable repair which include strength, compatibility and bond or adhesion are first discussed. Then the development, testing and field implementation of the aforementioned materials are discussed including the learning curve required to implement a repair system, not just install a new material. Some of the materials discussed, while expensive on a cost per unit basis, hold great promise for economical use on fast track project.

• Advances in concrete construction
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• v.5 no.2
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• pp.101-115
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• 2017

Cement kiln dust (CKD) is one of the most important waste materials in the cement industry. The large amount of this material, has encouraged researchers to propose new ways to recycle and reuse it. In this paper, effects of adding cement kiln dust to the ordinary Portland cement, on the physical and mechanical properties of ordinary and lightweight concrete were investigated. Results showed that concrete containing CKD, presents lower workability and modulus of elasticity; however, improvements in strength was observed by adding particular amounts of CKD. Eventually, it was found that adding 10% of cement weight CKD is the appropriate percentage for utilizing in manufacturing ordinary and lightweight concrete.

• 한국터널공학회:학술대회논문집
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• 2005.04a
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• pp.77-86
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• 2005

In urban areas, new tunnel construction work is often taking place adjacent to existing piled foundations. In this case, careful assessment for the pile-soil-tunnel interaction is required. However, research on this topic has not been much reported, and currently only limited information is available. In this study, the complex pile-soil-tunnel interaction is investigated using the upper and lower bound methods based on kinematically possible failure mechanism and statically admissible stress field respectively. It is believed that the limit theorem is useful in understanding the complicated interaction behaviour mechanism and applicable to the pile-soil-tunnel interaction problem. The results are compared with numerical analysis. The material deformation patterns and strain data from the FE output are shown to compare well with the equivalent physical model tests. Admissible stress fields and the failure mechanisms are presented and used to develop upper and lower bound solutions to assess minimum support pressures within the tunnel.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.487-492
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• 2003

High-strength concrete(HSC) is a new construction material with enormous potential. Structures using high-strength concrete are to be coming more and more popular. But high-strength reinforced concrete columns show brittle behavior. It, therefore, is necessary to improve the ductility of HSC members. The purpose of this study is to investigate the ductility and strength of high-strength columns with variable lateral confinement under concentric axial load. Five HSC columns with compressive strength 68㎫ are designed with variable lateral confinements such as carbon fiber sheet(CFS), glass fiber sheet(GFS), and metal lath. Test results indicate that specimen confined by CFS show 11% higher maximum strength, 2.74 times ductility than A specimen using hoop. On comparing with the specimen A and B confined metal lath instead of hoop, strength decrease of 3%, and ductility increase of 1.21 times were observed.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.4 no.4
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• pp.215-220
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• 2000

This study on the incineration ash and sintering pellet from sewage sludge was carried out to evaluate the possibility of recycling in sewage sludge disposal. The samples used in this experiment were raw sewage sludge, its incineration ash, and sintering pellet. The characteristics of the three sample types were identified using X-ray diffraction(XRD), X-ray fluorescence(XRF), atomic absorption spectroscopy(AAS), and inductively coupled plasma spectroscopy(ICP). The chemical compositions of all three sample types were similar in their clay component, however, the sewage sludge had a high content of organic materials. From an analysis of the mineral content of the three sample types, the conversion of their compositions was found to be relative to temperature. Accordingly, incineration ash and sintering pellet both have potential for use as a functional construction material.

• Journal of Drive and Control
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• v.9 no.1
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• pp.18-24
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• 2012

The paper deals with the design of a new low-friction seal for a pneumatic cylinder with high speed actuation. The seal performance with variation of the cross sections in piston seals with elastomeric material was investigated to minimize the friction forces using ABAQUS. The contact stress and strain distributions and frictional forces of the piston seals were investigated with variation of interference fits, supply pressures and friction coefficients. To develop adequate and productive procedures, the finite element models of the piston seals were created and nonlinear analysis of a seal design was conducted in order to build further knowledge and understanding of the seal's performance characteristics.

• Steel and Composite Structures
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• v.16 no.3
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• pp.289-303
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• 2014

In recent, development of construction and design technology gives taller, larger and heavier steel framed structures. With the tendency of increasing high-rise building, this study is strongly related to structural system, one of significant components in structural design. This study presents an innovative structural system, with high performance steel material, diagrid. Its detail, structural analysis, and structural experiments are all included for the development of new structures.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.8
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• pp.573-580
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• 2002

Generally the ceiling frame of apartment house is made of wood. But the wood frame has several problems due to the natural properties such as distortion by shrink, low fire resistance and material loss in the construction field. And it has some defections in sound insulation performance. Therefore it is necessary to develop a new method that can be used as a ceiling frame. This study aims to analyze and to compare the sound insulation characteristics against the floor impact sound between wood ceiling frame and M-bar frame which is made of steel. The results of this study are like these. M-bar frame is more effective than wood ceiling frame in sound insulation. And sound absorbing or sound insulation materials which can be Put on gypsum board are helpful to improve floor impact sound insulation performance.