• Advances in concrete construction
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• v.10 no.3
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• pp.257-269
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• 2020

The aim of this study is to investigate the flexural performance of hybrid fiber reinforced self-compacting concrete (HFRSCC) having different ratio of micro and macro steel fiber. A total of five mixtures are prepared. In all mixtures, the sum of the steel fiber content is 1% and also water/binder ratio is kept constant. The amount of high range water reducer admixture (HRWRA) is arranged to satisfy the workability criteria of self-compacting concrete. Four-point bending test is carried out to analyze the flexural performance of the mixtures at 28 and 56 curing days. From the obtained load-deflection curves, the load carrying capacity, deflection and toughness values are investigated according to ASTM C1609, ASTM C1018 and JSCE standards. The mixtures containing higher ratio of macro steel fiber exhibit numerous micro-cracks and, thus, deflection-hardening response is observed. The mixture containing 1% micro steel fiber shows worst performance in the view of all flexural parameters. An improvement is observed in the aspect of toughness and load carrying capacity as the macro steel fiber content increases. The test results based on the standards are also compared taking account of abovementioned standards.

• Smart Structures and Systems
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• v.14 no.4
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• pp.501-516
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• 2014

The rocking pier system (RPS) allows the columns to rock on beam or foundation surfaces during the attacks of a strong earthquake. Literatures have proved that seismic energy dissipated by the RPS through the column impact is limited. To enhance the energy dissipation capacity of a RPS bridge substructure, frictional hinge dampers (FHDs) were installed and evaluated by shaking table tests. The supplemental FHDs consist of two brass plates sandwiched by three steel plates. The strategy of self-centering design is to isolate the seismic energy by RPS at the columns and then dissipate the energy by FHDs at the bridge deck. Component tests of FHD were first conducted to verify the friction coefficient and dynamic characteristic of the FHDs. In total, 32 shaking table tests were conducted to investigate parameters such as wave forms of the earthquake (El Centro 1940 and Kobe 1995) and normal forces applied on the friction dampers. An analytical model was also proposed to compare with the tested damping of the bridge sub-structure with or without FHDs.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.291-293
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• 2012

Recently, environmental pollution and global warming and greenhouse gases are increasing, because Efforts to improve are continued throughout the world. As part of the resource recycling industry has become an important research area. In the field of waterproofing industry, focus on the resource recycling is growing, due to serious resource depletion and sharp price. Therefore, in this research on the resource recycling such as reclaimed rubber and rubber waste is enable and these eco-friendly materials are applied high adhesive flexible non-exposed type self adhesion compound waterproofing material was measured eco-friendly performance and field application was evaluated.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2007.11a
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• pp.91-94
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• 2007

It is essential every concrete structure should continue to perform its intended functions, that is maintain its required strength and durability, during the service life. However, deterioration occurs more progressively from the outside of concrete exposed to severe conditions. Deterioration in the concrete structure is due to carbonation and chloride ion attack. Therefore, concrete structure is needed to surface protection for increase durability using impregnant. Impregnant classify into two large groups in polymeric and silicate materials. Silicate impregnant is included silane and alkali silicate(sodium and lithium silicate). Thus, this study is concerned with carbonation and chloride ion resistance of self cleaning hydrophilic impregnant of concrete structure using lithium and potassium silicate. From the experimental test result, lithium and potassium silicate have a good properties as a carbonation and chloride ion resistance. Lithium and potassium silicate make good use of hydrophilic impregnant.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.203-204
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• 2019

Recently, exposed concrete designs have been placed everywhere due to increased interest in indoor residential environments. In addition, in order to overcome the disadvantages of litracon, which was developed by mixing optical fiber, LEFC(Light Emotion Friendly Concrete) was developed in Korea, which improved unit price and constructivity by inserting hard acrylic rods. LEFC, using foaming agent and lightweight aggregate for light weighting, has disadvantages that decrease mechanical properties, and thus improved mechanical properties by using ultra-high performance concrete. Also, due to the characteristics of UHPC materials, it showed excellent self-consolidating performance. Considering these characteristics, a LEFC mold with pattern design was developed. The LEFC blocks were built so that pattern shapes could be seen and these were applied on-site to Sewoon plaza, located in Seoul.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.166-167
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• 2015

The purpose of this study is to examine the effect on drying shrinkage of self-healing epoxy-modified mortars(EPMMs) using expansive admixtures. The EPMMs are prepared with polymer-binder ratios of 0 and 10%, and tested for drying shrinkage and pore structure analysis. As a result, regardless of the expansion and swelling agent content, the drying shrinkage of the EPMMs is remarkably decreased than that of unmodified mortars. Also, the pore size distribution of the EPMMs is moved to smaller size in comparison with unmodified mortars. In this study, the EPMM with expansive agent 7.5% and swelling agent 2.5% is recommended as a optimal mix proportion for reduction of drying shrinkage.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.173-174
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• 2018

In this study, the objective of this study was to evaluate the adhesive characteristics of existing self-adhesive rubber asphalt sheet, butyl sheet and acrylate sheet in a low temperature environment through Tack Rolling Ball Test to obtain basic data on acrylate. As a result of this experiment, in the case of the self-molding rubber asphalt sheet and the butyl rubber sheet, the compound of the sheet was frozen in the low temperature environment and the iron bead was separated. On the other hand, the acrylate sheet did not freeze the acrylate even at 0 ℃, It is confirmed that the measured value is shown by Ball Test.

• Journal of the Korea Safety Management & Science
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• v.5 no.3
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• pp.11-20
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• 2003

An agriculture which is one of the national security industry, has recognized the importance. International country have attention to the automatization of machine for the improvement of agriculture. However, because of modernization of agriculture, the rate of accurrence about agriculture accident has increased dramatically. Especially the rate of accurence of agricultural accident is higher than the other industrial accident in the developed country. Because of these reasons, developed country has efforted to the agriculture system about safety. Australia law for the safety system of agriculture is very well and the rate of accident in the self-management agriculture is included in the statistics of industrial But The rate of accident in self-management agriculture is very higher In future we have to try new method about Agricuture Safety of Korea.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.1022-1030
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• 2003

In this paper we propose a efficient offset curve construction algorithm for $C^0$-continuous Open and Closed 2D sequence curve with line segment in the plane. One of the most difficult problems of offset construction is the loop problem caused by the interference of offset curve segments. Prior work[1-10] eliminates the formation of local self-intersection loop before constructing a intermediate(or raw) offset curve, whereas the global self-intersection loop are detected and removed explicitly(such as a sweep algorithm[13]) after constructing a intermediate offset curve. we propose an algorithm which removes global as well as local intersection loop without making a intermediate offset curve by forward tracing of tangential circle. Offset of both open and closed poly-line segment sequence curve in the plane constructs using the proposed approach.

• 월간 기계설비
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• no.2 s.199
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• pp.66-70
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• 2007

벽산건설(주)은 1958년‘한국스레트공업주식회사’로 출발하여 우리나라 경제성장 시기를 함께하며 발전해왔다. 1991년 벽산건설(주)로 상호를 변경, 현재까지 국내 건설부문의 일익을 담당하고 있다. 벽산건설(주)은 특히 아파트 건설부문에서 두각을 나타내고 있다. 2005년 벽산건설(주)의 아파트 브랜드인“블루밍”에 대해 SDP(Self Design Project)를 런칭해 그동안 일률적이던 아파트 내부 건축에 대해 변화를 줘 고객에게‘자신만의 아파트’라는 이미지를 심어준 것이다. 끊임없이 발전하려는 벽산건설(주)의 노력이 지금의 벽산건설(주)을 만들게 된 원동력이다. 벽산건설(주)은 2007년을“내실기반의 지속성장을 하는 해”로 설정하고 올해 경영방침을 △수익기반의 다변화 △고객 만족 경영 △Software 경쟁력 강화로 정했다. 이에 따른 구체적인 경영전략으로 △전략적 제휴확대로 양질의 수주 확보 △Before Service 전사적 확대 △인적자원 경쟁력 강화 △핵심기술의 확보 및 개발 등 더 나은 기술과 고객만족을 위해 오늘도 정진하고 있다.