• 제목/요약/키워드: combined load

검색결과 1,123건 처리시간 0.027초

3차원 수치해석을 통한 복합하중이 작용하는 농업용저수지의 거동 분석 (Analysis of Behavior of Agricultural Reservoir with Combined Load by 3-D Numerical Analysis)

  • 송창섭;우제근;안광국;김명환
    • 한국농공학회논문집
    • /
    • 제60권1호
    • /
    • pp.59-65
    • /
    • 2018
  • The object of this paper was to analyze combined load acting on agricultural reservoir. This study was carried out to 3-D numerical modeling for displacement characteristic and seismic acceleration characteristic. The results of study were analyzed and summarized as follow. It was found that the displacement caused by combined load acting on railway and agricultural reservoir did not reflect the effect of load and the seismic wave consistently. The ground accelerations that occur in railway and dam were amplified because 3-D numerical analysis program interprets ground as an elastic body. Actual ground shows characteristics of elasticity and plasticity, so measured values will show different tendency. As a result of analyzing displacement characteristics, it is considered to be related to stiffness. The Ofunato seismic wave, the displacement (77.1 mm) of the body satisfied the allowable displacement (220 mm), but The Hachinohe seismic wave (282.8 mm) did not. It is considered that displacement caused by combined load is affected not only by acceleration but also by characteristics of materials.

압력과 모멘트의 복합하중을 받는 곡관의 소성 붕괴하중 예측식 개발 (Closed-Form Plastic Collapse Loads of Pipe Bends Under Combined Pressure and In-Plane Bending)

  • 오창식;김윤재
    • 대한기계학회논문집A
    • /
    • 제30권8호
    • /
    • pp.1008-1015
    • /
    • 2006
  • Based on three-dimensional (3-D) FE limit analyses, this paper provides plastic limit, collapse and instability load solutions for pipe bends under combined pressure and in-plane bending. The plastic limit loads are determined from FE limit analyses based on elastic-perfectly plastic materials using the small geometry change option, and the FE limit analyses using the large geometry change option provide plastic collapse loads (using the twice-elastic-slope method) and instability loads. For the bending mode, both closing bending and opening bending are considered, and a wide range of parameters related to the bend geometry is considered. Based on the FE results, closed-form approximations of plastic limit and collapse load solutions for pipe bends under combined pressure and bending are proposed.

비강우시 도시 합류식 하수도의 오염부하 산정을 위한 최적관측시간 산정연구 (Optimum Flow and Pollution Load Monitoring Time of Combined Sewers of Urban Watersheds during Dry Weather)

  • 최용훈;원철희;박운지;서지연;신민환;이찬기;최중대
    • 한국농공학회논문집
    • /
    • 제51권3호
    • /
    • pp.9-14
    • /
    • 2009
  • Flow and pollution load were monitored at 2 combined sewer outlets (C-1 and C-2) of urban watersheds during dry weather from September, 2004 to April, 2006 for 20 months. The objectives were to investigate the diurnal variation of flow and pollutant load and to find the proper sampling time that could measure representative flow and pollutant load. Pollution load closed to the average daily load at C-1 could be measured at 00:00 hour and by the mean of 15:00 and 18:00 hour measures, and 15:00 and 21:00 hour measures, respectively. In addition at C-2, it was 21:00 hour and the mean of 15:00 and 18:00 hour measures. This study concluded that arbitrary sampling of flow and water quality could cause large errors in the estimation of urban pollution load and recommended that urban combined sewers should be monitored when flow and water quality showed daily average and concentration.

조합하중을 받는 원통형 곡판구조의 좌굴 및 최종강도 거동에 관한 연구 (A Study on the Buckling and Ultimate Strength for Cylindrically curved plate subject to combined load)

  • 오영철;고재용;이경우
    • 한국항해항만학회:학술대회논문집
    • /
    • 한국항해항만학회 2007년도 추계학술대회 및 제23회 정기총회
    • /
    • pp.25-26
    • /
    • 2007
  • Ship are typically thin-walled structures and consists of stiffened plate structure by purpose of required design load and weight reduction etc. Also, a hull structural characteristics are often used in structures with curvature at deck plating with camber, side shell plating at fore and aft parts and bilge circle parts, It have been believed that these structures can be modelled fundamentally by a part of cylinder. Structural component with curvature subjected to combined loading regimes and complex boundary conditions, which can potentially collapse due to buckling. Hence, for more rational and safe design of ship structures, it is crucial importance to better understand the interaction relationship of the buckling and ultimate strength for cylindrically curved plate under these load components. In this study, the ultimate strength characteristic of curved plate under combined load(lateral pressure load + axial compressive load) are investigated through using FEM series analysis with varying geometric panel properties.

  • PDF

공간 트러스에 대한 효율적인 비선형 해석 기법 제안 (The Proposition of Efficient Nonlinear Solution Technique for Space Truss)

  • 석창목;권영환
    • 한국전산구조공학회논문집
    • /
    • 제15권3호
    • /
    • pp.481-490
    • /
    • 2002
  • 본 논문의 목적은 공간 트러스 비선형 해석기법에 대한 수치해석적 장단점을 비교하고, 효율적인 해석기법을 제안하는 것이다. 사용된 해석기법은 하중 제어법으로 뉴턴-랩슨법, 수정 뉴턴-랩슨법, 할선-뉴턴법, 하중-변위 제어법으로 호장법, 증분일 제어법, 그리고 본 논문에서 제안한 하중-변위의 복합적 제어법으로 복합 호장법 Ⅰ, 복합 호장법Ⅱ, 복합 증분일 제어법이 있다. 공간 트러스에 대한 해석기법의 효율성 평가를 위하여 해의 정확성, 수렴성, 계산시간 등을 제시된 예에 비교한 결과 본 논문에서 제안한 하중-변위의 복합적 제어법의 신뢰성을 입증하였으며, 기하학적 비선형 해석 및 좌굴후 거동의 추적에 있어서 효율적이었다. 특히, 자유도수가 많은 공간 트러스의 좌굴하중 추척에 있어서는 복합 증분일 제어법이 효율적이었다.

A new model for T-shaped combined footings part II: Mathematical model for design

  • Luevanos-Rojas, Arnulfo;Lopez-Chavarria, Sandra;Medina-Elizondo, Manuel
    • Geomechanics and Engineering
    • /
    • 제14권1호
    • /
    • pp.61-69
    • /
    • 2018
  • The first part shows the optimal contact surface for T-shaped combined footings to obtain the most economical dimensioning on the soil (optimal area). This paper presents the second part of a new model for T-shaped combined footings, this part shows a the mathematical model for design of such foundations subject to axial load and moments in two directions to each column considering the soil real pressure acting on the contact surface of the footing with one or two property lines restricted, the pressure is presented in terms of an axial load, moment around the axis "X" and moment around the axis "Y" to each column, and the methodology is developed using the principle that the derived of the moment is the shear force. The classic model considers an axial load and a moment around the axis "X" (transverse axis) applied to each column, i.e., the resultant force from the applied loads is located on the axis "Y" (longitudinal axis), and its position must match with the geometric center of the footing, and when the axial load and moments in two directions are presented, the maximum pressure and uniform applied throughout the contact surface of the footing is considered the same. To illustrate the validity of the new model, a numerical example is presented to obtain the design for T-shaped combined footings subjected to an axial load and moments in two directions applied to each column. The mathematical approach suggested in this paper produces results that have a tangible accuracy for all problems.

해양구조물 원통부재의 최종강도에 대한 손상의 영향 (Damage Effects on the Ultimate Strength of Offshore Tubular Members)

  • 백점기;신병천
    • 한국해양공학회지
    • /
    • 제3권2호
    • /
    • pp.577-577
    • /
    • 1989
  • In this paper, a detail evaluation of ultimate strength of offshore unstiffened tubular members with bending and local denting damage which are subjected to combined axial force and bending moment and to component load is presented through theoretical and experimental approaches. Based upon the results obtained here, the damage effect on the ultimate strength of tubular member under combined loads and component load is investigated.

해양구조물 원통부재의 최종강도에 대한 손상의 영향 (Damage Effects on the Ultimate Strength of Offshore Tubular Members)

  • 백점기;신병천
    • 한국해양공학회지
    • /
    • 제3권2호
    • /
    • pp.77-86
    • /
    • 1989
  • In this paper, a detail evaluation of ultimate strength of offshore unstiffened tubular members with bending and local denting damage which are subjected to combined axial force and bending moment and to component load is presented through theoretical and experimental approaches. Based upon the results obtained here, the damage effect on the ultimate strength of tubular member under combined loads and component load is investigated.

  • PDF

표면 열전달율의 복사.대류성분 분리와 비정상 열부하 계산에 관한 연구 (A Study on the Radiation and Convection Component Separated from Surface Combined Heat Transfer Coefficient on Dynamic Heat Load Simulation)

  • 김영탁;최창호
    • 한국태양에너지학회 논문집
    • /
    • 제25권3호
    • /
    • pp.1-9
    • /
    • 2005
  • The purpose of this paper was to analyze the influence of radiation and convection component separated from surface heat combined transfer coefficient on dynamic Heat load simulation. In general, it was not considered the mutual radiation of walls that heat load simulation calculated by surface combined heat transfer coefficient. In order to solve this problem, we had developed new simulation program to calculate radiation heat transfer and convection heat transfer respectively, and verified the influence of radiation component with this new program, in indoor heat transfer process.

압력과 모멘트의 복합하중을 받는 곡관에 대한 유한요소 한계하중 해석 (Limit Loads for Pipe Bends under Combined Pressure and in-Plane Bending Based on Finite Element Limit Analysis)

  • 오창식;김윤재
    • 대한기계학회논문집A
    • /
    • 제30권5호
    • /
    • pp.505-511
    • /
    • 2006
  • In the present paper, approximate plastic limit load solutions fur pipe bends under combined internal pressure and bending are obtained from detailed three-dimensional (3-D) FE limit analyses based on elastic-perfectly plastic materials with the small geometry change option. The present FE results show that existing limit load solutions for pipe bends are lower bounds but can be very different from the present FE results in some cases, particularly for bending. Accordingly closed-form approximations are proposed for pipe bends under combined pressure and in-plane bending based on the present FE results. The proposed limit load solutions would be a basis of defective pipe bends and be useful to estimate non-linear fracture mechanics parameters based on the reference stress approach.