• 제목/요약/키워드: Static load test

검색결과 994건 처리시간 0.028초

정적 및 피로시험에 의한 틸팅열차용 볼스터의 구조강도평가 (Strength Evaluation for Bolster of Korean Tilting Train by Static and Fatigue Tests)

  • 김남포;김정석
    • 대한기계학회논문집A
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    • 제30권2호
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    • pp.210-218
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    • 2006
  • This paper has performed static, fatigue and nondestructive test of tilting' bolster frame for Korean tilting train. From the static test, the structural safety was investigated using Goodman diagram. After the static test, the fatigue test were conducted under tilting load conditions. The fatigue test was conducted for $10\times10^6$ cycles. During the fatigue test, the nondestructive tests using magnetic particle and liquid penetrant were performed at $6\times10^6$cycle and $10\times10^6$cycle. From the crack detection tests, it was known that there was no fatigue crack in the tilting bolster.

강섬유 보강 철근콘크리트보의 신뢰성 해석 (Reliability Analysis of Steel Fiber Reinforced Concrete Beams)

  • 유한신;곽계환;장화섭
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2004년도 봄 학술발표회 논문집
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    • pp.479-486
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    • 2004
  • The purpose of this study is to practical use with increase safety, usablility and economical. In this study, the property of fatigue behavior was tested by comparing reinforced concrete and steel fiber reinforced concrete. The basic test, the static test and fatigue test were used as the research methods. Basic on the test, the material compressive strength test and split tensile strength test ware conducted 7 days and 28 days after the concrete was poured. In the static test, there ware four types of experimental variables of the steel fiber mixing ratio : 0.00%, 0.75%, 1.00%, and 1.25%. The ultimate load initial diagonal tension crack, and initial load of flexural cracking were all observed by static test. A methodology for the probabilistic assement of steel fiber reinforced concrete(SFRC) which takes into account material variability, confinement model uncertainty and the uncertainty in local and globa failure criteria is applied for the derivation of vulnerability curves for the serviceability and ultimate limit states, the reliability of SFRC using the proposed practical linear limit state model is evaluated by using the AFOSM(Advanced First Order Second Moment) method and MCS(monte-Calrosimulation) method.

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동적 단열재를 적용한 건물에서의 에너지소비량 비교 분석 (Heating Power Consumption Comparison Study Between Static Insulation and Dynamic Insulation at KIER Twin Test Cell)

  • 강은철;박용대;이의준;윤태권
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2008년도 하계학술발표대회 논문집
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    • pp.919-924
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    • 2008
  • Power consumption in the building thermal load could be the sum of the building fabric conduction load, building ventilation convection load and other such as radiation loss load. Dynamic Breathing Building (DBB) is the state-of-the-art to improve the wall insulation and indoor air quality(IAQ) performance as making air flow through the wall. This heat recovery type DBB contributes the power consumption saving due to the improved dynamic U-value. KIER twin test cell with static insulation(SI) and dynamic insulation(DI) at KIER was developed to test building power consumption at the real outside conditions. Then, the actual results were compared with the theory to predict the power consumption at the KIER twin test cell and introduced the building new radiation loss factor $\alpha$ to explain the difference between the both the theory and the actual case. As the results, the power consumption at the breathing DI wall building could saved 10.8% at the 2ACH(Air change per hour) compared with conventional insulation. The building radiation loss factor $\alpha$ for this test condition to calibrate the actual test was 0.55 in the test condition.

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평균 응력을 고려한 음향 하중을 받는 항공기 센서 포드 외피 구조의 내구 수명 분석 (Fatigue Life Prediction for the Skin Structures of Aircraft Sensor Pod Under Acoustic Load with Mean Stress)

  • 전민혁;김연주;조현준;이미연;김인걸;이한솔;조재명;배종인;박기영
    • 한국군사과학기술학회지
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    • 제26권1호
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    • pp.1-9
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    • 2023
  • The skin structure of sensor pod mounted on the exterior of aircraft can be exposed to the acoustic dynamic load and static load such as aerodynamic pressure and inertial load during flight. Fatigue life prediction of structural model under acoustic load should be performed and also differential stiffness of model modified by static load should be considered. The acoustic noise test spectrum of MIL-STD-810G was applied to the structural model and the stress response power spectral density (PSD) was calculated. The frequency response analysis was performed with or without prestress induced by inplane static load, and the response spectrum was compared. Time series data was generated using the calculated PSD, and the time and frequency domain fatigue life were predicted and compared. The variation of stress response spectrum due to static load and predicted fatigue life according to the different structural model considering mean stress were examined and decreasing fatigue life was observed in the model with prestress of compressive static load.

매입 개단 강관말뚝의 하중분담률과 침하량 분석 연구 (A Study on the Load Sharing Ratio and the Settlement of Prebored Open-Ended Steel Pipe Piles)

  • 김채민;김기환;윤도균;최용규
    • 한국지반신소재학회논문집
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    • 제22권1호
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    • pp.39-51
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    • 2023
  • 매입말뚝의 지지력은 많은 연구자들에 의해 연구되었다. 하지만 하중분담률과 침하량에 대하여 설계 자료와 말뚝재하시험 지료를 비교한 연구는 미미하였다. 그래서 매입 개단 강관말뚝에 대하여 설계식 자료와 정재하시험 결과를 비교하였다. 압축재하시험에서는 선단지지하중과 주면마찰하중의 분담률이 각각 13%~40%, 60%~87%로 나타났고, 이때의 침하량은 2.2mm~4.7mm로 측정되었다. 현행 지지력 산정식에서는 선단지지력과 주면마찰력이 각각 54%~75%, 25%~46%를 분담하는 것으로 나타났고, 침하량은 19.8mm~23.6mm로 계산되었다. 현행지지력 산정식에서의 침하량은 시험에서의 침하량보다 321%~776% 만큼 크게 나타났으며, 평균적으로 445%만큼 크게 나타났다. 말뚝재하시험에서의 하중분담률을 이용하여 침하량을 산정하면, 시험 침하량보다 137%~525% 만큼 크게 나타났으며, 평균적으로 204% 만큼 크게 나타났다. 하중분담률의 적절한 평가는 말뚝 기초의 침하량 산정에 중요한 영향을 미치는 것으로 확인되었다.

분산형 고속전철의 하중조건에 따른 정적 하중시험 평가 (The Structural Analysis and Experimental Verification for the Next Generation High Speed EMU)

  • 최정용;정원화;박근수;우관제
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2011년도 춘계학술대회 논문집
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    • pp.307-313
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    • 2011
  • Hyundai Rotem Company has designed and manufactured the next generation high speed EMU bodyshell (M3-car). Korean Railway Safety Law specifies the loads vehicle bodies shall be capable of withstanding, identifies what material data shall be used and presents the principles to be used for design verification by analysis. Therefore, in order to fulfill the structural requirements, Hyundai Rotem Company has carried out Finite Element Analysis (FEA) and static load test to verify whether the carbody structure has enough strength to withstand the loads specified by Korean Railway Safety Law. This research contains the results obtained by the FE analysis and static load test. The FE analysis is carried out using NX I-DEAS 6.1 and specially designed test jigs and equipment are used for the load tests.

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항타강관말뚝과 현장타설말뚝의 주면마찰력 거동에 관한 현장실험 연구 (A Study on Friction Capacity Behavior for Driven Steel Pipe Pile and Drilled Shaft Pile with Field Test)

  • 정성민;이민희;송병덕;최용규
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2005년도 춘계 학술발표회 논문집
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    • pp.1-8
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    • 2005
  • In this study, static pile load tests for instrumented drilled shaft pile and instrumented driven steel pipe pile were performed. Based on the results of pile load test, skin friction of each stratum was compared. Skin friction of drilled shaft were more than those of driven pile at the same settlement. This was based on the difference of surface roughness of piles and pile construction methods.

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피로하중을 받는 유리섬유 보강 플라스틱관의 안전성에 관한 연구 (An Experimental Study on the Safety of Glass Fiber Reinforced Plastic Pipes under Fatigue Load)

  • 채원규
    • 한국안전학회지
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    • 제11권3호
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    • pp.154-159
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    • 1996
  • In this thesis, a series of loading tests are conducted in order to investigate the fracture safety of GFRP(Glass Fiber Reinforced Plastics) pipes under fatigue load which are widely used in the developed countries becauses of their natural of anticorrosion and lightweight etc. . Fatigue test is performed by changing number of laminates and loading cycles to examine the flexural strains, the ductility and the fatigue strength for two million repeated loading cycles. From the fatigue test results, it was found that the larger the laminates of GFRP pipes is, the larger the stiffness of GFRP pipes under the fatigue load increases. This phenomenon is true until the fatigue failure. According to the S-N curve drawn by the regression analysis on the fatigue test results, the fatigue strength of percent of the static ultimate strength increases by increasing the laminates of GFRP pipes. The fatigue strength with two million repeated leading cycles in GFRP pipes with the laminates of GFRP pipes varing 15, 25, 35 shows about 75%, 80%, 84% on the static ultimate strength, respectively.

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Static and fatigue behavior of through-bolt shear connectors with prefabricated HFRC slabs

  • He, Yuliang;Zhuang, Jie;Hu, Lipu;Li, Fuyou;Yang, Ying;Xiang, Yi-qiang
    • Structural Engineering and Mechanics
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    • 제83권1호
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    • pp.109-121
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    • 2022
  • Twelve push-out test specimens were conducted with various parameters to study the static and fatigue performance of a new through-bolt shear connector transferring the shear forces of interface between prefabricated hybrid fiber reinforced concrete (HFRC) slabs and steel girders. It was found that the fibers could improve the fatigue life, capacity and initial stiffness of through-bolt shear connector. While the bolt-hole clearance reduced, the initial stiffness, capacity and slippage of through-bolt shear connector increased. After the steel-concrete interface properties were improved, the initial stiffness increased, and the capacity and slippage reduced. Base on the test results, the equation of the load-slip curve and capacity of through-bolt shear connector with prefabricated HFRC slab were obtained by the regression of test results, and the allowable range of shear force under fatigue load was recommended, which could provide the reference in the design of through-bolt shear connector with prefabricated HFRC slabs.

재하시험에 의한 PHC 매입말뚝의 저항계수 산정 II (Estimation of resistance coefficient of PHC bored pile by Load Test II)

  • 박종배;박용부;권영환
    • 토지주택연구
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    • 제9권3호
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    • pp.1-8
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    • 2018
  • 유럽과 미국에서는 말뚝기초 설계에 한계상태설계법 사용이 거의 정착되었으며, 세계적 추세에 따라 국내에서도 국토해양부가 한계상태설계법에 기반한 교량하부기초 설계기준을 제정하였지만, 국내 말뚝공법 및 지반조건에 대한 저항계수 연구가 부족하여 당장 설계에 반영하기에는 어려운 여건이었다. 이에 본 연구에서는 국내에서 많이 사용되고 있는 PHC 매입말뚝의 저항계수를 구하기 위하여 LH설계기준과 도로교설계기준 방법으로 산정한 지지력과 LH 현장에서 실시한 정재하시험(21회)과 동재하시험(EOID 21회, Restrike 21회) 결과를 신뢰성분석을 실시하였으며, 선행 논문(재하시험에 의한 PHC 매입말뚝의 저항계수 산정)에서 수행한 결과보다 2배 이상 많은 데이터를 추가하여 분석하였다. 그 결과 정재하지지력(극한)으로 구한 저항계수는 설계식 및 목표신뢰도지수에 따라 0.64~0.83, 동재하지지력(극한)으로 구한 저항계수는 0.42~0.55로 나와 정재하지지력(극한)으로 구한 저항계수보다 약 33% 작게 나타났다. 반면 수정동재하지지력(EOID의 극한선단지지력 + Restrike의 극한주면지지력)으로 구한 저항계수는 0.55~0.71로 나와 정재하지지력(극한)으로 구한 저항계수와 비교 시 그 차이가 약 14%로 줄어들었다. 데이터 추가에 의해 저항계수를 산정한 결과 이전 저항계수와 같거나 0.04정도 증가하여 데이터가 2배 이상 추가되어도 저항계수가 의미 있을 정도로 크게 변하지 않은 것으로 나타났다. 결론적으로 본 연구에서 정재하 및 동재하시험으로 산정한 전체 저항계수는 전반적으로 도로교설계기준(2015)에서 제시한 저항계수 0.3보다 커서 경제적인 설계가 가능한 것으로 나타났다.