• Journal of the Earthquake Engineering Society of Korea
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• v.9 no.1 s.41
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• pp.33-42
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• 2005

Even in moderate to low seismic regions like Korean peninsular where wind loading usually governs the structural design of a tall builidng, the probable structural impact of the 500-year design basis earthquake (DBE) or the 2400-year maximum credible earthquake (MCE) on the selected structural system should be considered at least in finalizing the design. In this study, seismic performance evaluation was conducted for concentrically braced steel highrise buildings that were only designed for wind by following the assumed domestic design practice. It was found that wind-designed concentrically braced steel highrise buildings possess significantly increased elastic seimsic capacity due to the system overstrength resulting from the wind-serviceability criterion and the width-to-thickness ratio limits on steel members. The strength demand-to-strength capacity study based on the response spectrum analysis revealed that, due to the system overstrength factors mentioned above, wind-designed concentrically braced steel highrise buildings having a slenderness ratio of larger than six can withstand elastically even the maximum credible earthquake at the performance level of immediate occupancy.

• Fire Science and Engineering
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• v.22 no.3
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• pp.239-245
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• 2008

In this study, we researched about characteristics of many kinds of tank cars for carrying hazard materials and performed structural strength evaluation using finite element analysis for tank of asphalt tank car to suggest the efficient analysis method that can develop accuracy regarding to characteristics of tank cars. For this, we analyzed the asphalt tank refer to JIS E 7102 (Design Method for Tanks of Tank Cars). As results, we could show that the maximum stress is applied at the area supported by saddle and the maximum stress is under a criterion suggested from JIS E 7102. Therefore we verified that this asphalt tank car had enough structural strength.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2017.11a
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• pp.278-279
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• 2017

북한 대부분이 미계측 지역으로서 자연재해 연구의 기초 데이터인 기상정보가 매우 부족한 실정이다. 이러한 지역은 천리안 기상위성 등 원격탐사 기술을 활용하여 재해 모니터링을 하여야한다. 천리안 기상위성은 기상청에서 운영하는 강우 알고리즘을 이용하면서 재해예측 보다는 일반적인 강우 예보에 중점을 두고 있다. 따라서 기상청 강우 알고리즘은 35 mm/hr를 초과하는 강우에 대해서는 탐지를 하지 못하므로 홍수위험 모니터링에 적합하지 않다. 본 연구에서는 이러한 문제를 해결하기 위해 기존의 천리안 강우강도 알고리즘에 GPM 위성 산출물(L3)과 같은 다중센서 자료를 적용하여 홍수유발 강우까지 측정할 수 있는 추정기술을 개발하였다. 개발된 강우 추정기술은 한국의 기상관측지점 94개소 자료와 비교 검증했을 때, 상관계수가 0.6 이상으로 기존의 알고리즘보다 개선된 강우를 추정할 수 있었다. 따라서 기존의 천리안 강우강도 알고리즘에서 추정하지 못했던 집중호우나 태풍의 강우강도를 정확하게 추정할 수 있으므로 미계측 지역의 홍수위험 모니터링에 도움이 될 것이다.

• Journal of Korean Society of Steel Construction
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• v.26 no.1
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• pp.31-42
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• 2014

In this paper, concrete-filled steel tubular columns encased with precast reinforced concrete were studied. Four eccentrically loaded columns and a concentrically loaded column were tested to investigate the axial load-carrying capacity. The test parameters were the use of fiber reinforcement for cover concrete, eccentricity, column length, and lateral reinforcement. The maximum axial loads of the specimens agreed with the nominal strengths predicted by KBC 2009. However, in some specimens, the load carrying capacity quickly decreased after the peak strength due to spalling of the cover concrete.

• 한국가스학회:학술대회논문집
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• 1997.09a
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• pp.39-44
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• 1997

한국가스공사에서 건설중이거나 관리중인 천연가스 주배관의 길이는 날로 크게 증가하고 있다. 이배관의 건전성확보를 위한 배관 재료물성 및 용접부위 특성 평가를 다양하게 실시하였다. 그 결과 현재 사용중인 배관은 모재와 각종 용접공정에 의한 용접부위의 기계적 특성이 각종 규격에서 제시하고 있는 권고치를 초과하는 높은 안전성을 보이고 있으며, 금속 조직 및 강도학적인 측면에서 충분한 건전성을 확보하고 있음을 알 수 있었다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.253-253
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• 2004

방전가공은 현재의 정밀 금형산업에서는 필수적인 가공방법이나, 공작물과 전극사이에서 방전이 발생할 때 고온고압의 플라즈마 상태에서 재료를 제거하는 메카니즘에 대한 해석은 아직도 많은 연구 대상이다. 방전가공은 기본적으로 3단계의 과정으로 구별할 수 있는데, 첫째 공작물과 전극의 간격과 기하학적 형상, 전압에 의해서 전계가 집중되어 절연체의 절연강도보다 초과하면 절연체가 이온화되어 방전이 시작된다. 둘째, 전극과 공작물이 통전이 되어 플라즈마 채널이 형성되면서 열에너지에 의하여 공작물이 용융 증발이 발생한다.(중략)

• Proceedings of the Korean Fiber Society Conference
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• 2001.10a
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• pp.151-153
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• 2001

링정방법은 생산유연성이 크고 생산된 제품의 물성이 우수하여 다른 공법에서 생산된 제품의 품질표준이 되며 가장 많이 이용되고 있는 공법이다. 이 기술은 스핀들과 회전자의 회전에 의하여 꼬임을 부여하며, 동시에 실을 권취한다. 그러나 스핀들 회전이 증가하면, 정방장력이 증가하므로써 섬유속 (실)의 절단강도를 초과하여 사절현상이 나타나게 된다. (중략)

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.135-135
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• 2004

• Journal of the Korea Concrete Institute
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• v.19 no.1
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• pp.103-111
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• 2007

Experimental study was carried out to investigate the structural performance of composite beams with steel fiber concrete and angle. For this purpose, seven specimens composed of two RC beams with or without steel fiber and five composite beams with steel fiber and angle were constructed and tested. All specimens had no web shear reinforcement. Main variables for the specimens were tensile reinforcement ratio and fiber volume fraction. Based on the test results, structural performance such as strength, stiffness, ductility and energy dissipation capacity was evaluated and compared with the predicted strength. The prediction of flexure and shear strength gives a good relationship with the observed strength. The strength, ductility and energy dissipation capacity are increased, as the fiber volume fraction is increased. Meanwhile, high tensile reinforcement ratio resulted in the reduction of ductility and energy dissipation capacity for the composite beams.

• Journal of the Korea institute for structural maintenance and inspection
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• v.27 no.3
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• pp.47-57
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• 2023

In this study, pull-out tests were performed to investigate the effects of stirrup spacing, rebar diameter, and corrosion rate on bond strength of deformed bars in reinforced concrete. Twelve pull-out specimens with different stirrup spacing, rebar diameter, and corrosion rate were prepared following the RILEM RC6 guidelines. The test results showed that the bond strength of specimens with stirrups increased when the corrosion rate was less than 3%, whereas it decreased when the corrosion rate was more than 3%. On the other hand, the bond strength of specimens without stirrups decreased as the corrosion rate increased. The effect of rebar diameter was less significant compared to those of stirrup spacing and corrosion rate. A bond strength model for pull-out specimens was proposed considering stirrup ratio and corrosion rate, and the model showed the lowest error among the previous models.