• Proceedings of the Korean Society of Disaster Information Conference
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• 2023.11a
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• pp.241-243
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• 2023

아파트 신축공사 흙막이 가시설 현장에 근접 매설된 상수관의 누수 및 파열 사고로 터파기 공사 현장에 토사 유실 및 지반 함몰이 발생되었으며, 흙막이 가시설의 토류판이 파손되었다. 흙막이 가시설의 안정성 확보를 위해 벽체구간은 레이커로 보강하고 사보강재는 1단과 2단을 묶어 힘을 분산시키고 종방향으로 보강 및 토류판 보강을 시행하였다.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.353-358
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• 2004

Tracing the study of the burst test of steam generator tube, few studies have been reported to effect of external pressure acting on secondary-side in service condition. In this study the burst tests of Inconel 690TT were conducted in order to evaluate burst strength characteristics under the effect of external pressure. We obtained the result that the burst strength of Inconel 690TT increased when external pressure increased while both total circumferential elongation and uniform burst elongation were not affected. Also, according to the increased of external pressure, the size of the burst opening became smaller and the tear was getting severe.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.219-222
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• 2009

Pyrostarters play a role as a turbopump starter in liquid propellant propulsion systems by supplying pressurized gas to power turbines for engine start. A rupture disk in pyrostarters, which is usually installed behind a nozzle throat, not only isolates the charged solid propellants from the external environment but also improves the ignitability of the solid propellants by increasing a chamber pressure at the beginning of combustion. Experimental tests have been performed to study the effects of rupture disk thickness, depth and shape of scores, and pressure build-up rates on burst pressures and burst diameters. The experimental results show that the developed rupture disk fulfills the performance requirements expected in a real operational condition.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.7 no.1
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• pp.9-16
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• 2009

Transport package for radioactive material should be structurally safe under puncture drop condition and its safety should be verified by test and numerical analysis. Most finite element analyses for puncture drop have been performed without modeling the impact limiter since failure is occurred in the materials of the impact limiter. This paper presents a new modeling methodology, where an element is eroded in case that the material's failure criteria are reached at the element's integration point, to investigate the effect of the impact limiter in the puncture process. The effectiveness of the proposed scheme is shown through the puncture drop analysis of hotcell transport cask, which is under design in KAERI. The results show that about 80 percent of the total impact energy is absorbed due to the deformation of impact limiter. Using the present method the puncture drop can be analyzed more accurately, but it would give conservative results compared to the actual test condition.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.288-292
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• 2008

Dome shape design method of filament wound (FW) composite pressure vessel, which can create various dome shape with fixed boss opening, was suggested. And, the performance indices (PV/W) for composite pressure vessel with same boss opening but different dome shape were investigated by finite element analysis (FEA) and hydro-test. The FEA showed good agreement with test results for burst pressure. Generally, as the dome shape of pressure vessel was changed to flat dome, the inner volume is increased and the burst pressure is decreased. In the case of above ${\rho}_o$=0.54, the performance index showed decreased value due to the low burst pressure. However, at ${\rho}_o$=0.35, the dome shape change brings not significant reduction of burst pressure and performance index.

• Aerospace Engineering and Technology
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• v.9 no.1
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• pp.72-77
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• 2010

A hydraulic test on a filament wound case of Kick-Motor was conducted to evaluate the structural stiffness degradation and to confirm the burst performance. Failure criteria have been defined with bursting above 150% of MEOP(Maximum Expected Operation Pressure) and failure in the cylinder. The analysis result showed that filament fiber in the cylinder should be broken at about 2088psig. From a hydraulic test it has been verified that composite case meets the failure requirements, and that the stiffness does not decrease even after a year since the manufacturing.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.9
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• pp.1131-1136
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• 2011

This study is performed on the acoustic emission parameters involved in a burst test for a CNG-vehicle fuel tank. A resonant AE sensor with a central frequency of 150 kHz was attached on the composite materials in the center of the fuel tank. The analysis of AE parameters such as hit, amplitude, count, duration, risetime, and signal strength during load holding was performed. The total count and total signal strength are effective tools for the damage evaluation of a CNG fuel tank.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.42 no.9
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• pp.745-751
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• 2014

For the multi-nozzle propulsion, the rupture pressure of nozzle closure has an effect on the initial strain rate of ignition. Moreover, the deviation of rupture pressure for each nozzle closure leads to side forces which can disturb the attitude control of rocket. When designed, it should be considered whether nozzle closures are ruptured equally and exactly in the intented pressure. In this paper, the rupture behavior is analyzed by analytical and experimental methods for plate and "+" notched nozzle closures. The rupture pressure and deviation for operating temperature, whether notched or not and notched directions are analyzed. This paper provides a comparison between rupture pressure prediction of finite elements method which tool is Abaqus/Explicit and results of the rupture test. Jonson-Cook shear failure model which corresponds to the damage initiation criterion were used in this simulation.

• Journal of Korean Society of Steel Construction
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• v.30 no.2
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• pp.67-76
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• 2018

An experimental study was conducted to evaluate the breakout strength of stirrup-reinforced cast-in anchors under dynamic shear loadings. The shear loadings were applied in the manner specified in the ACI 355.2 and ETAG 001 for the seismic qualification tests. Test specimens were fabricated with M36 anchor (edge distance, 180mm) reinforced with D10 stirrups (spacing, 100mm). The specimens reached almost the breakout strength and thereafter fracture of anchor occurred. Additional tests with M42 anchor (edge distance, 160mm) reinforced with D6 bars (spacing, 100mm) were also conducted. The experimental results showed that the dynamic shear strength was not less than the static resistance. Based on the test results, it was shown that ACI 318 and ETAG 001 specifications estimate the breakout strength of stirrup-reinforced anchors conservatively as more reinforcement is provided.

• 한국전기화학회:학술대회논문집
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• 2005.07a
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• pp.201-206
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• 2005

본 연구는 기 개발 완료된 천연가스차량용 200bar급 Type 3 복합재 압력용기를 개발로 축척된 핵심요소기술과 실질적인 경험을 바탕으로 수소연료전지 차량에 탑재할 350bar급 Type 3 복합재 압력용기에 대한 설계/해석과 시험평가의 핵심적인 사항을 고찰하였다. 설계/해석에는 350bar급 Type 3 복합재 압력용기에 대한 3차원 비선형 유한요소 모델링 및 해석기법이 제시되었고, 설계된 라이너형상과 와인딩 패턴을 이용하여 필라멘트 와인딩 공법으로 1차시제품을 제작하였다. 제작된 시제품에 대하여 파열시험 및 반복피로시험을 수행하여 설계/해석 기법의 타당성을 검증하였다.