• 제목/요약/키워드: combined loads

검색결과 485건 처리시간 0.025초

수평하중하에서 철근 콘크리트 플랫 플레이트의 구조적 거동에 관한 실험적 연구 (Experimental Study on the Structural Behaviors of Reinforced Flat Plate Under Lateral Loads)

  • 조영직;박성무
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1995년도 가을 학술발표회 논문집
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    • pp.323-328
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    • 1995
  • This paper is experimental study to define the structural behaviors of reinforced flat plate under combined gravity and lateral loads. Specific objectives of this study reported herein are : (1) To study the behavior of a typical slab-column subassemblage under lateral loading. (2) To study the effects of vertical loads on slab-column lateral load behavior. (3) To investigate the post-failure behavior of slab-column connetios. To achieve these objectives, this study includes four tests of slab-column subassemblages that were made for 1/2 scale. Finally, Test results of this study show that the level of gravity load on the flat plate is one of the most important factors determining the lateral behavior of flat plate connections.

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감육이 존재하고 내압과 굽힘하중의 복합하중을 받는 T 분기관의 한계하중 (Limit Loads for Piping Branch Junctions with Local Wall-thinning under Internal Pressure and In-plane Bending)

  • 한재준;이국희;김윤재;이성호;박치용
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회A
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    • pp.299-304
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    • 2008
  • This paper presents plastic limit loads of piping branch junctions with local wall thinning under combined pressure and in-plane bending, based on systematic three-dimensional finite element limit analyses using elastic-perfectly plastic materials. An ideal branch junction without weld or reinforcement around the intersection is considered with two locations of wall thinning; one in the run pipe, and the other in the branch pipe. Based on FE results, effects of thinning geometries on plastic limit moments are quantified and simple approximations of plastic limit loads are proposed.

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Measuring hull girder deformations on a 9300 TEU containership

  • Koning, Jos;Schiere, Marcus
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제6권4호
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    • pp.1111-1129
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    • 2014
  • A 9300 TEU container carrier was equipped in 2006 with instrumentation aimed at wave induced accelerations, and motions. In 2010 the system was extended with strain sensors to include structural loads. Section loads for vertical bending could be readily obtained but the originally intended derivation of horizontal bending and torsion from the measured strains was found to be unreliable. This paper addresses an alternative approach that was adopted in the post processing of results. In particular the concept to use acceleration sensors to capture global hull deformations along the length of the hull, and the use of a data fusion procedure to obtain section loads from combined sensor data and finite element calculations. The approach is illustrated by comparison of actually measured accelerations and local strains with values obtained from the data fusion model. It is concluded that the approach is promising but in need of further validation and development. In particular the number and shapes of the modes used may not have been sufficient to represent the true deflection and thus strain distributions along the high loaded areas.

Fatigue Strength of Fillet Welded Steel Structure Under Out-of-plane Bending Load

  • Kang, S.W.;Kim, W.S.;Paik, Y.M.
    • International Journal of Korean Welding Society
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    • 제2권1호
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    • pp.33-39
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    • 2002
  • The effect of out-of-plane loads on the fatigue strength of welded steel structures is examined through fatigue tests with weldment of two fillet weld joint types. The results of the fatigue tests are compared with those under axial loads, on the basis of the hot spot stress range at the weld toe. From the result of the comparison, a method on how to incorporate the effect of the out-of-plane bending stress is proposed using design S-N curves derived from fatigue tests under the axial load. The proposed method is useful for rational assessment of the fatigue strength of fillet-welded structures, where combined stresses of the in-plane axial stress and the out-of-plane bending stress are induced simultaneously due to the complexity of applied loads and structural geometry.

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실지진 모사를 위한 조합형 정현하중의 적용성 검증 (Verification of Combined Sinusoidal Loads for Simulating Real Earthquakes)

  • 최재순
    • 대한토목학회논문집
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    • 제39권6호
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    • pp.811-819
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    • 2019
  • 2016년 경주지진과 2017년 포항지진이 발생한 이후, 우리나라 내진설계에 있어서 다양한 실내진동시험의 수행이 증가하고 있으나, 액상화 평가나 수치해석의 입력파라미터를 산정하기 위한 실내진동시험에서는 이전부터 사용해 오던 정현하중의 이용이 계속되고 있다. 그러나, 최근 정현하중으로는 지진하중으로 야기되는 지반 내 과잉간극수압의 거동을 정확하게 모사하기 어렵다는 연구결과가 발표되며 정현하중을 대신하여 동하중의 개발에 대한 논의가 주목을 받기 시작하였다. 이 연구에서는 이러한 문제를 해결하고자 조합형 정현하중을 제안하고 주문진 표준사를 대상으로 한 진동전단실험과 진동삼축압축시험을 통해 그 적용성을 검토하였으며 추가로 진동대시험과 유효응력해석모델에 기초한 수치해석을 통해 그 타당성을 검토하였다. 검토 결과, 제안된 조합형 정현하중이 정현하중보다 실지진하중 하에서의 포화지반 내 과잉간극수압의 거동변화를 잘 모사할 수 있음을 발견하였다.

복합하중을 받는 평판에 존재하는 반타원 표면균열의 공학적 탄소성 파괴해석법 (Engineering Elastic-Plastic Fracture Analysis for Semi-Elliptical Surface Cracked Plates Under Combined Bending and Tension)

  • 심도준;김윤재;최재붕;김영진
    • 대한기계학회논문집A
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    • 제26권6호
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    • pp.1127-1134
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    • 2002
  • The present paper provides an engineering J estimation equation for surface cracked plates under combined bending and tension. The proposed equation is based on the reference stress approach, and the most relevant normalising loads to define the reference stress for accurate J estimations are given for surface cracked plates under combined bending and tension. Comparisons with J results from extensive 3-D FE analyses, covering a wide range of crack geometry, plate geometry and loading combination, show overall good agreement not only at the deepest point but also at arbitrary points along the crack front. for pure tension, agreement between the estimated J and the FE results is excellent, even at the surface point. On the other hand, for pure bending and combined bending and tension, the estimated J values become less accurate for locations close to the surface point. Thus the results in this paper will be useful to assess short-term fracture or low cycle fatigue of surface defects in plates under combined bending and tension.

중공축 소재를 이용한 전후방 복합압출의 성형 특성 (Forming Characteristics of the Forward and Backward Tube Extrusion Using Pipe)

  • 김성현;이호용
    • 소성∙가공
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    • 제14권9호통권81호
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    • pp.772-778
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    • 2005
  • This paper is concerned with the analysis of material flow characteristics of combined tube extrusion using pipe. The analysis in this paper concentrated on the evaluation of the design parameters for deformation patterns of tube forming, load characteristics, extruded length, and die pressure. The design factors such as punch nose radius, die corner radius, friction factor, and punch face angle are involved in the simulation. The combined tube extrusion is analyzed by using a commercial finite element code. This simulation makes use of pipe material and punch geometry on the basis of punch geometry recommended by International Cold Forging Group. Deformation patterns and its characteristics in combined forward and backward tube extrusion process were analyzed for forming loads with primary parameters, which are various punch nose radius relative to backward tube thickness. The results from the simulation show the flow modes of pipe workpiece and the die pressure at the contact surface between pipe workpiece and punch. The specific backward tube thickness and punch nose radius have an effect on extruded length in combined extrusion. The combined one step forward and backward extrusion is compared with the two step extrusion fer forming load and die pressure.

Fiber reinforced concrete L-beams under combined loading

  • Ibraheem, Omer Farouk;Abu Bakar, B.H.;Johari, I.
    • Computers and Concrete
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    • 제14권1호
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    • pp.1-18
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    • 2014
  • The addition of steel fibers in concrete mixture is recognized as a non-conventional mass reinforcement scheme that improves the torsional, flexural, and shear behavior of structural members. However, the analysis of fiber reinforced concrete beams under combined torsion, bending, and shear is limited because of the complicated nature of the problem. Therefore, nonlinear 3D finite element analysis was conducted using the "ANSYS CivilFEM" program to investigate the behavior of fiber reinforced concrete L-beams. These beams were tested at different reinforcement schemes and loading conditions. The reinforcement case parameters were set as follows: reinforced with longitudinal reinforcement only and reinforced with steel bars and stirrups. All beams were tested under two different combined loading conditions, namely, torsion-to-shear ratio (T/V) = 545 mm (high eccentricity) and T/V = 145 mm (low eccentricity). Eight intermediate L-beams were constructed and tested in a laboratory under combined torsion, bending, and shear to validate the finite element model. Comparisons with the experimental data reveal that the program can accurately predict the behavior of L-beams under different reinforcement cases and combined loading ratios. The ANSYS model accurately predicted the loads and deformations for various types of reinforcements in L-beams and captured the concrete strains of these beams.

사질토 지반에 위치한 해상풍력발전기 석션기초의 복합하중에 대한 안전성 평가 (Safety Evaluation of the Combined Load for Offshore Wind Turbine Suction Foundation Installed on Sandy Soil)

  • 박정선
    • 한국해안·해양공학회논문집
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    • 제33권5호
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    • pp.195-202
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    • 2021
  • 해상풍력발전기는 바람 및 파도, 구조물 자중에 의해 수직-수평-모멘트의 복합하중을 받는다. 본 연구에서는 유한요소해석으로 사질토 지반에 설치된 해상풍력발전기 석션기초의 복합하중에 대한 지지력을 산정하였다. 또한 복합하중이 작용하는 중의 석션기초 주변 지반의 응력상태를 상세하게 분석하였다. 최종적으로 유한요소해석 결과를 토대로 수평 및 모멘트 지지력 산정식과 복합하중에 대한 안전성을 평가하는 지지력 포락선 식을 제안하였다.

합류식 하수관거 지역에서 강우시 하수처리장 적정운영방안에 관한 연구 (Alternatives for The Stable Operation of Wastewater Treatment Plant in Combined Sewer System during Wet Weather)

  • 이두진;신응배;홍철의;안세영
    • 한국물환경학회지
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    • 제20권2호
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    • pp.132-144
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    • 2004
  • The purpose of this study was to evaluate alternatives for stable operation of WWTP(Wastewater Treatment Plant) with a higher rate of inflows and a higher concentration of pollutants during wet weather to minimize the pollution loads being discharged into receiving waters. 3Q(Q: dry weather flow) of a base flow is normally intercepted and flows into WWTP as it was current practice. It is revealed by simulation that the bypassing alternative of 1Q through secondary treatment and 2Q into the stream after primary treatment was as good as it is expected. The bypass pollution loads were in the range of 23.9 ~ 38.5 % of the total loads flowing into the WWTP indicating that the bypassed flows need an extra treatment such as stormwater detention reservoir, high-rate coagulation with sedimentation, and step-feed. The high-rate coagulation with sedimentation was the most effective with respect to removal of the pollution loads.