• The Monthly Technology and Standards
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• s.12
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• pp.67-78
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• 2003

In order to keep a characteristic corrugated fibreboard of fruits and flowers, temperature and humidity change of corrugated fibreboard are analyzed. According to relative humidity rises at fixed temperature, bursting strength of corrugated fibreboard was fallen and double wall corrugated fibreboard appeared greatly the bursting strength decline rate than double faced corrugated fibreboard and edgewise compressive strength of paper more than humidity 80% in rapidly fall. A column crush test of paper became decrease in the high temperature and ordinary temperature strength did over humidity 70% rapidly fallen and strength decrease happened by low temperature 80% slowly fallen and later rapidly. According to ISO standard temperature humidity conditioning (23$\pm$2 , 50$\pm$2%) change, pulp composition difference as to the ring crush strength of a physical strength and generally compare to KS standard increased 5∼8% for the compressive strength, and wet strength reagent was increased 4% inside and out.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.39 no.5
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• pp.391-399
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• 2011

The purpose of this paper is to predict the shock absorbing characteristics of the aluminum honeycomb in a lunar lander. Aluminum honeycomb has been used for shock absorbers of lunar lander due to its characteristics such as light weight, high energy absorption efficiency and applicability under severe space environments. Crush strength of the honeycomb should have strength to endure during shock energy absorbing process. In this paper, the crush strength, which depends on the shape of honeycomb and impact velocity, is estimated using FEM. Ls-dyna is used for finite element analysis of the honeycomb shock absorber. The unit cells of the honeycomb shape are modeled and used for the finite element analysis. Energy absorption characteristics are decided considering several conditions such as impact velocity, foil thickness and branch angle of the honeycomb.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2002.05a
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• pp.51-55
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• 2002

The production accounts of domestic by-product is increased after 1990's. It is worried about the life reduction of dump land, as dump land's capacity have reached to limitation and the amount of construction industrial wastes is going higher Recently, Recycling aggregates could be gained from the reconstruction works using recycle process. and the study and research of recycle concretes developed concrete application methods, It could put some outcome of studies to practical use for concrete products. The methods of crushing waste concrete are going diverse. In this study, the fundamental experiments and recycling application is investigated and analyzed with use of recycling aggregate which made of mechanical crush and underwater electrical impact crush. and the difference between underwater electrical impact crush, mechanical crush and natural aggregates is studied.

• International Journal of Highway Engineering
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• v.5 no.4 s.18
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• pp.37-47
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• 2003

Song-E(scoria) is civil material that we frequently meet with in road building in Jeju-island. It is known that Song-E is the material of high crush and large particle. But, the study on the scoria is not enough, so there are many difficult in handling method. In this study, We research basic strength characteristics on Song-E gathered at various part in Jeju-island. Results of this study(strength characteristics of Song-E) are applied to design of road, breast wall and slope as basic data.

• Journal of the Korea Institute of Building Construction
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• v.3 no.1
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• pp.123-129
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• 2003

The production accounts of domestic by-product is increased after 1990's. It is worried about the life reduction of dump land, as dump land's capacity have reached to limitation and the amount of construction industrial wastes is going higher. Recently, recycling aggregates could be gained from the reconstruction works using recycle process, and the study research of recycle concretes developed concrete application methods. It could put some outcome of studies to practical use for concrete products. The methods of crushing waste concrete are going diverse. In this study. the fundamental experiments and recycling application is investigated and analyzed with use of recycling aggregate which made of mechanical crush and underwater electrical impact crush, and the difference between underwater electrical impact crush, mechanical crush and natural aggregates is studied.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.3
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• pp.47-53
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• 1999

The effect of coating of liner components with oxidized starch on the properties of corrugated box was examined . Coating was carried out on liner components of B flute, single-wall corrugated board(SK180/S120/K200) , and corrugated box was made from the treated corrugated board. Box was made in a regular slotted container (RSC) style, and box compression strength was determined in the direction of top-to-bottom compression. The compression strength of box coated on outside liner component showed 15.4% improvement for 1.58g㎡ coating. On the other hand, the strength of box coated on outside liner component showed only 1.45% improvement for 1.41g/㎡ coating and 3.46% improvement for 2.32g/㎡ coating. Coating on inside liner component with oxidized starch at low coating weight more significantly improved box compression strength than coating on outside liner component, and the improvement was marked at the coating weight of 1.5-2.5g/㎡. In estimating top-to-bottom box compression strength, the experimental values were closer to the calculated values from McKee's equation suing edgewise compression strength of the combined board measured by column crush test than those from Kellicutt's equation using compression strength of component paperboards measured by ring crush test.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.7 no.2
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• pp.43-51
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• 2001

This study was carried out to analyze changes of the physical properties of corrugated fiberboard boxes for fruits packaging by various moisture and temperature changes. There were significant decrease in burst strength with increased relative humidity. And also compressive strength(ring crush test) of corrugated fiberboard and box were reduced with moisture content. The decreasing amounts of single wall(SW) corrugated fiberboard was bigger than that of double wall(DW). The physical properties reductions of corrugated fiberboard and box were mainly affected by relative humidity. Therefore, it is suggested that development of the water-resistant corrugated fiberboard and box be useful under the condition of low temperature and high relative humidity such as the cold chain system.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.41 no.5
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• pp.8-14
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• 2009

Corrugated fiberboard is a widely used packaging material because of its high compressive strength and stiffness despite light weight. Corrugated fiberboards with microflutes with height $\leq$ 1.5 mm, such as E, F or G, have been developed. As microflutes have a different geometry from other conventional flutes, they may behave differently in testing and require a new testing method. Therefore, we evaluated the flat crush resistance of corrugated fiberboard with microflutes according to the ISO and TAPPI standard test methods. In addition, the effects of specimen area and platen compression rate were examined. The goal of this study was to identify an appropriate method for flat crush test (FCT) of corrugated fiberboard with microflutes. When a test piece with a standard area was subjected to the FCT in accordance with ISO and TAPPI methods, microflute corrugated fiberboard demonstrated a different load-displacement curve. An area of 20 $cm^2$ was determined to be the most appropriate for FCTof microflute corrugated fiberboard.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.305-308
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• 2007

The spacer grid assembly is one of the main structural components of the nuclear fuel assembly of a PWR. The spacer grid assembly supports and aligns the fuel rods, guides the fuel assemblies past each other during handling and, if needed, sustains lateral seismic loads. The ability of the spacer grid assembly to resist the lateral loads is usually characterized in terms of its dynamic and static crush strengths, which are acquired from tests. In this study, a finite element analysis on the dynamic crush strength of spacer grid assembly specimens is carried out and compared with test results.

• Journal of the KSME
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• v.35 no.8
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• pp.709-715
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• 1995

날로 그 중요성이 대두되고 있는 환경보존 문제에 능동적으로 대응하고 여러 계층 소비자의 안 전도, 쾌적성 등에 관련된 요구, 성능의 수준향상에 효과적으로 대처하기 위해서는 차량의 경량화 기술이 가장 먼저 선행되어야 할 과제이다. 경량화를 추구하는 방법은 최적설계 개념을 이용한 구조합리화에 의한 방법과 알루미늄, 강화 플라스틱 등 신소재 대체에 의한 방법이 병행 연구 되고 있다. 이 글에서는 구조합리화를 통한 경량화 목표를 달성하기 위해 설계 초기 단계에 활용 가능한 단순 보 모델 개발의 필요성에 관해 언급하고 실차의 도어 측면 붕괴강도(door side intrusion strength), 루프 붕괴강도 (roof crush strength) 해석을 위한 단순 보 모델 개발에 관해 소개하고자 한다.