• 제목/요약/키워드: Load testing

검색결과 1,270건 처리시간 0.031초

Interface friction in the service load assessment of slab-on-girder bridge beams

  • Seracino, R.;Kerby-Eaton, S.E.;Oehlers, D.J.
    • Steel and Composite Structures
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    • 제5권4호
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    • pp.259-269
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    • 2005
  • Many slab-on-girder bridges around the world are being assessed because they are approaching the end of their anticipated design lives or codes are permitting higher allowable loads. Current analytical techniques assume that the concrete and steel components act independently, typically requiring full-scale load testing to more accurately predict the remaining strength or endurance of the structure. However, many of the load tests carried out on these types of bridges would be unnecessary if the degree of interaction resulting from friction at the steel-concrete interface could be adequately modeled. Experimental testing confirmed that interface friction has a negligible effect on the flexural capacity of a slab-on-girder beam however, it also showed that interface friction is significant under serviceability loading. This has led to the development of an improved analytical technique which is presented in this paper and referred to as the slab-on-girder mixed analysis service load assessment approach.

주행모드에 따른 전기이륜차의 1회충전주행거리 시험방법에 관한 연구 (Per-Charge Range-Testing Method for Two-Wheeled Electric Vehicles)

  • 길범수;김강출
    • 대한기계학회논문집A
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    • 제38권1호
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    • pp.37-44
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    • 2014
  • 본 연구에서는 전기이륜차의 1회충전주행거리를 알아보기 위해 도로 주행시험과 차대동력계(Chassis Dynamometer) 주행시험을 하였다. 도로주행시험은 대전시(Daejeon Metropolitan City)의 도로 중 대표적인 3가지 루트에서 주행시험을 하였다. 차대동력계를 이용한 CVS-40모드 주행시험의 경우 도로 부하조건을 다양하게 설정하여 CVS-40 모드주행을 실시하였다. 본 연구를 통하여 도로에서의 전기이륜차의 1회 충전주행거리(Per-Charge Range Testing)를 확인하고, 차대동력계 도로부하 설정방법에 따른 주행거리 및 에너지소비효율을 측정하였다. 이를 통해 실도로 주행시험과 차대동력계 주행시험을 비교하여, 차대동력계 실험에서도 전기이륜차 1회충전주행거리시험이 실도로에서의 주행조건과 근접한 결과를 갖는 도로부하 설정에 대해 연구하였다.

Geotechnical Parameter Assessment for Tall Building Foundation Design

  • Poulos, Harry G.;Badelow, Frances
    • 국제초고층학회논문집
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    • 제4권4호
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    • pp.227-239
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    • 2015
  • This paper discusses the design parameters that are required for the design of high-rise building foundations, and suggests that the method of assessment for these parameters should be consistent with the level of complexity involved for various stages in the design process. Requirements for effective ground investigation are discussed, together with relevant in-situ and laboratory test techniques for deriving the necessary strength and stiffness parameters. Some empirical correlations are also presented to assist in the early stages of design, and to act as a check for parameters that are deduced from more detailed testing. Pile load testing is then discussed and a method of interpreting bi-directional tests to obtain pile design parameters is outlined. Examples of the application of the assessment process are described, including high-rise projects in Dubai and Saudi Arabia.

Assessment of load carrying capacity and fatigue life expectancy of a monumental Masonry Arch Bridge by field load testing: a case study of veresk

  • Ataei, Shervan;Tajalli, Mosab;Miri, Amin
    • Structural Engineering and Mechanics
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    • 제59권4호
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    • pp.703-718
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    • 2016
  • Masonry arch bridges present a large segment of Iranian railway bridge stock. The ever increasing trend in traffic requires constant health monitoring of such structures to determine their load carrying capacity and life expectancy. In this respect, the performance of one of the oldest masonry arch bridges of Iranian railway network is assessed through field tests. Having a total of 11 sensors mounted on the bridge, dynamic tests are carried out on the bridge to study the response of bridge to test train, which is consist of two 6-axle locomotives and two 4-axle freight wagons. Finite element model of the bridge is developed and calibrated by comparing experimental and analytical mid-span deflection, and verified by comparing experimental and analytical natural frequencies. Analytical model is then used to assess the possibility of increasing the allowable axle load of the bridge to 25 tons. Fatigue life expectancy of the bridge is also assessed in permissible limit state. Results of F.E. model suggest an adequacy factor of 3.57 for an axle load of 25 tons. Remaining fatigue life of Veresk is also calculated and shown that a 0.2% decrease will be experienced, if the axle load is increased from 20 tons to 25 tons.

횡방향 하중을 받는 CFRF 적층복합재의 내부손상에 관한 연구 (A Study on the Damage of CFRP Laminated Composites Under Out-of-Plane Load)

  • 김문생;박승범;오득창
    • 한국정밀공학회지
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    • 제12권11호
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    • pp.98-109
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    • 1995
  • An investigation was performed to study the inner damage of laminated composite plates subjected to out-of-plane load. During the investigation, inpact velocity and equivalent static load relationship was derived. Reddy's higher-order shear deformation theory(HSDT) and Hashin's failure criteria were used to determine inner stresses and damaged area. And impact testing was carried out on laminated composite plates by air gun type impact testing machine. The CFRP specimens were composed of [ .+-. 45 .deg. ]$_{4}$and [ .+-. 45 .deg. /0 .deg. /90 .deg. ]$_{2}$ stacking sequences with 0.75$^{t}$ * 26$^{w}$ * 100$^{l}$ (mm) dimension. After impact testing. As a result, a relationship holds between damaged area and impact energy, and a matrix cracking was caused by the interlaminar shear stress in the middle ply and was caused by the inplane transverse stress in the bottom ply.

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경량전철차량 알루미늄 구조체 하중시험방법 연구 및 결과고찰 (A Study on The Load Test Method and Result For AL Car Body of LRT)

  • 김원경;원시태;전창성
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2008년도 춘계학술대회 논문집
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    • pp.986-995
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    • 2008
  • This study introduces the testing results of the AL car body which is applied to LRT. The LRT car body is made of aluminum structure materials like a sandwich panel. The static load test was performed to evaluate the structural characteristic and stability of the AL car body. Considering the vertical, compressive, twisting load and 3-point supporting, Bend natural frequency Measurement, Twist natural frequency Measurement type as a testing terms, the structural stability of a car body was evaluated.

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철도차량 알루미늄 차체 용접방법에 따른 하중시험결과 비교 고찰 (A Study on Comparison Of The load Test Results Of AL Car Body Welding Method For Rolling Stock)

  • 김원경;원시태;전창성
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2009년도 춘계학술대회 논문집
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    • pp.1604-1612
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    • 2009
  • This study introduces comparison the testing results of the AL car body which is applied to FSW and GMAW welding method. The car body is made of aluminum structure materials like a sandwich panel. The static load test was performed to evaluate the structural characteristic and stability of the AL car body. Considering the vertical, compressive, twisting load and 3-point supporting, Bend natural frequency Measurement, Twist natural frequency Measurement type as a testing terms, the structural stability of a car body was evaluated.

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Cyclic Load Testing of Concrete Expansion Anchors

  • Gary L. Barnes;Lee, Sang-Myung
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 춘계학술발표회논문집(4)
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    • pp.404-404
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    • 1996
  • In order to ensure a concrete expansion anchor is suitable for a given application, the load resistance behavior of the anchor must be known. ASTM E488 provides a standard method of testing expansion anchors for static and dynamic loads. Due to the many types of anchors available commercially and the large variability of applications, the ASTM does not delineate all details or requirements necessary to comprehensively determine the dynamic load behavior of concrete expansion anchors. A test program is presented in this paper which was developed and implemented to determine the cyclic load behavior of wedge-type concrete expansion anchors. Test results are also presented along with a discussion of the behavior of anchors, and their suitability for use.

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암석내 균열성장개시점의 결정을 위한 실험적 연구 (An experimental study on the determination of the crack initation load level in rock)

  • 김재동
    • 산업기술연구
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    • 제9권
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    • pp.43-49
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    • 1989
  • In this study, 3-point bending test for the mode I state and 4-point shear test for the mode II state were adopted to verify the crack initiation load level through comparing the test results of the acoustic emission and the ASTM testing criteria, using Jecheon granite, as the rock sample. The major result obtained in this study is that the crack initiation load levels obtained by using ASTM testing criteria and by measuring acoustic emissions showed analogous, roughly. However in case of demanding high safety, the crack initiation load level needs to be underestimated to the level that the crack begins to deform nonlinearly.

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Field distribution factors and dynamic load allowance for simply supported double-tee girder bridges

  • Kidd, Brian;Rimal, Sandip;Seo, Junwon;Tazarv, Mostafa;Wehbe, Nadim
    • Structural Engineering and Mechanics
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    • 제82권1호
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    • pp.69-79
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    • 2022
  • This paper discusses the field testing of two single-span double-tee girder (DTG) bridges in South Dakota to determine live load distribution factors (LLDFs) and the dynamic load allowance (IM). One bridge had seven girders and another had eight girders. The longitudinal girder-to-girder joints of both bridges were deteriorated in a way that water could penetrate and the joint steel members were corroded. A truck traveled across each of the two bridges at five transverse paths. The paths were tested twice with a crawl speed load test and twice with a dynamic load. The LLDFs and IM were determined using strain data measured during the field tests. These results were compared with those determined according to the AASHTO Standard and the AASHTO LRFD specifications. Nearly all the measured LLDFs were below the AASHTO LRFD design LLDFs, with the exception of two instances: 1) An exterior DTG on the seven-girder bridge and 2) An interior DTG on the eight-girder bridge. The LLDFs specified in the AASHTO Standard were conservative compared with the measured LLDFs. It was also found that both AASHTO LRFD and AASHTO Standard specifications were conservative when estimating IM, compared to the field test results for both bridges.