• KSCE Journal of Civil and Environmental Engineering Research
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• v.44 no.1
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• pp.33-39
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• 2024

This study explores the utilization of common marine wastes, specifically seashells, such as oysters and cockles, as alternative fine aggregates in construction materials. The considered seashells were cleaned and pre-processed for use as a substitute for aggregate in mortar. Cement mortar specimens were prepared under different conditions, such as substitution ratios and the cleaning status of the seashells. The compressive strength of the mortars specimens was evaluated, and the solid and porous structures of each specimen were analyzed using microstructure analysis methods such as XRD, SEM, and micro-CT. The results confirmed that oyster and cockle seashells are composed of different calcium carbonate polymorphs, and their microstructural characteristics influence the mechanical properties of the cement mortar specimens.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05b
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• pp.115-118
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• 2003

본 고에서는 현재 중국에서 추진되고 있는 고등교육 부문에 대한 진흥시책을 "211공정(工程)"을 중심으로 조망해보았다. 등소평의 중점대학 육성 구상에 따라 중국 국내의 제반 여건을 고려하여 "구오(九五)"기간 중에 개시된 "211공정(工程)"의 주요내용은 국가중점대학(國家重點大學)과 국가중점학과(國家重點學科) 건설 사업이다. 강역민(江澤民) 집권 후에는 "과교흥국(科敎興國)"을 기본국책으로 설정하여 교육부(敎育部)내의 과학기술사(科學技術司)에서 기지건설과 인재양성을 중점적으로 담당하면서 과학기술교육을 고등교육 발전의 기본축으로 삼아 적극적으로 추진하고 있다. 중국의 경우 이와 같은 국가 주도적인 진흥책을 중국공산당중앙위원회(중공중앙(中共中央))와 국무원의 방침 결정에 따라 집중육성(중점(中点)) 항목 결정 및 관리를 국무원 산하 유관부문이 상호 협조 하에 분담하여 지원하고 있다.

• Composites Research
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• v.19 no.3
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• pp.37-42
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• 2006

In the past, the technology of strengthening structures using FRP composites was still in its infancy, with very few publications on the technology available. However, recently strengthening of Reinforced concrete (RC) and other structures using advanced fibre-reinforced polymer/plastic(FRP) composites has become very popular in the last few years. As the well-known advantages of FRP composites including both good corrosion resistence and ease for site handling due to their light weight, also its design methods have been ensured the safe and economic use of this new technology, FRPs have been used widely and demonstrated in the field of aero industries etc. The purpose of this paper is to report the examples of the many diverse applications of Fiber Reinforced Plastic in construction materials of structures.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.59-60
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• 2021

To measure the effect of the stress-strain dispersion across the installed waterproofing layer on the concrete surface, a strain gauge was attached to the gap between the waterproofing layer and the concrete structure at specified points of upper, center and bottom of the load-displacement simulation specimen, and the peak stress-strain at the displacement interface were measured and compared with stress-strain at other areas to analyze each material types' stress-strain dispersion ratio properties. Based on the results of the testing, it was shown that materials with high load-displacement resistance performance accordingly had high stress-strain dispersion ratio results, and the materials from highest performance to lowest performance were; CAS, SAS, PUC and CSC.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.212-213
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• 2021

As structure and the waterproofing material are compressed through the backfilling process after the waterproofing material is installed on the underground structure at the actual site, there is a difference between the behavioral response force of the waterproofing material in the compressed state and the behavioral response force in the non-constrained state. In this regard, we will analyze the limitations of the current structural behavioral response evaluation and suggest an improvement plan so that the future test and evaluation environment can be evaluated under conditions similar to the field.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2023.11a
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• pp.135-136
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• 2023

본 논문에서는 건설현장 중 토목건설현장의 임시설비 기계, 기구 등의 접지저항치를 안전하게 최대한 낮추어 감전 재해율을 저감하기 위한 연구이며, 토목건설현장 주변의 설치되어 있는 기존 시설물 흙막이, 가드레일, 개천의 물 등을 이용한 접지시설을 통해 각종 사용되는 임시설비의 감전재해 저감을 위함이다. 최근 건설현장 안전관리에 대한 임시설비 등의 기계화, 안전장치 등의 발전에도 불구하고, 건설현장의 감전 재해율은 크게 감소하지 않는 추세라 이를 보완, 보호하기 위해 본 논문을 작성하였다. 건설현장 중 접지시설 설치가 곤란하고 어려운 토목건설현장 대상으로 감전재해 형태의 예방효과를 별도의 재료를 필요로 하지 않고 현장 주변 시설물 대상을 이용한 접지시설을 설치하여 실제로 실험을 통해 접지저항치에 대해 측정하였다.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.43 no.1
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• pp.1-7
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• 2023

A set of foamed concrete specimens with different densities were prepared, and several microscopic techniques, such as scanning electron microscope (SEM) and X-ray micro-computed tomography (micro-CT) were used to characterize the foamed specimens. The pore and solid characteristics of the specimens at different ages were examined to investigate the effect of aging on the materials. The compressive strength and the thermal conductivity of the foamed specimens were also evaluated, and the relationship between the material characteristics and properties was integrated to identify the effect of density and aging on the material properties.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.211-212
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• 2023

Polishing tiles among porcelain tiles are more durable and aesthetic than ceramic tiles, so their demand has recently increased. In particular, since polishing tiles have a very low absorption rate, organic adhesives with chemical bonds are mainly used. However, organic adhesives have low economic efficiency and some volatile organic compounds (TVOCs). Therefore purpose of this study was to evaluate the performance of polishing tile adhesion by developing organic-inorganic adhesives, which have chemical bonds and mechanical bonds. As a result, since the amorphous chain and chemical bonds of the polymer in the tile adhesives, both tensile and shear adhesion strength were satisfied with the KS L 1592, KS L 1593, and the rate of length change itself in the thermal cycling was lower than organic adhesives. So it is thought that it is possible to replace some organic adhesives.

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.6
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• pp.84-90
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• 2016

Various form of membrane structures are being built in recent years. However, there is no appropriate fire proofing standards which can be applied each specific membrane structures. Therefore, existing fire protection standards are in establishment state and they need to be revised. In the current study, commonly used membrane materials(ETFE, PVF, PTFE) has been selected to investigate its fire resistance behavior with the change of fire duration time. In addition to this, heat generation rate of the membrane materials in correlation with the height of membrane has been investigated. And these fire combustion characteristics of membrane materials can be used in future practice for the fire prevention regulations of membrane structures.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.3
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• pp.311-321
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• 2021

Many studies have been performed on hybrid fiber reinforced concrete for years, which is to improve some of the weak material properties of concrete. Studies on characteristics of hybrid fiber reinforced concrete using amorphous steel fiber and organic fiber, however, yet remain to be done. The purpose of this research is to evaluate the compressive and tensile behaviors and then propose a material model of high performance hybrid fiber reinforced concrete using amorphous steel fiber and polyamide fiber. For this purpose, the high performance hybrid fiber reinforced concretes were made according to their total volume fraction of 1.0% for target compressive strength of 40MPa and 60MPa, respectively, and then the compressive and tensile behaviors of those were evaluated. Also, based on the experimental results of the high performance hybrid fiber reinforced concrete and mortar, each material model for the compressive and tensile behavior was suggested. It was found that the experimental results and the proposed models corresponded relatively well.