• Title/Summary/Keyword: compressive force

Search Result 608, Processing Time 0.028 seconds

압축력 및 토오크가 회전축의 휨진동 특성에 미치는 영향 (Effect of Compressive Force and Torque on Lateral Vibration Characteristics of Rotor System)

  • 홍장표;한동철
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 1990년도 추계학술대회논문집; 한양대학교, 서울; 24 Nov. 1990
    • /
    • pp.199-203
    • /
    • 1990
  • 본 연구에서는 일반적인 형상을 갖는 회전축에서 축 방향 하중과 토오크를 각각 또는 동시에 고려할 수 있는 전달 행렬을 수식화하였고, 이에 의한 진 동 특성을 해석하기 위하여 강제진동 해석 및 자유진동 해석을 수행하였으 며, 해석결과에 대한 신빙성을 얻기 위하여 과도진동 해석 및 이산화 FFT를 통하여 검산기능을 추가하였다. 그리고 전달 행렬법에 새로운 고유치 수치해 법과 수치 적분법의 적용을 통하여 `수렴성과 안정성을 개선하였다.

  • PDF

구조적 성능 향상을 위한 철차 하부 지지틀의 고찰 (The Review of Underframe Structure to Improving Structual Performance)

  • 최원호;김운호;엄경수
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2007년도 춘계학술대회 논문집
    • /
    • pp.1571-1577
    • /
    • 2007
  • Nowadays stronger rules are applied to rolling stocks because of improvement of standards and thoughts to safety. So the designing lightweight rolling stock underframe structure is required to these rules. This review is about underframe structure which satisfies the condition of AAR Longitudinal static compressive force 360 ton comparing with difference of the former underframe structure.

  • PDF

PHC 파일의 재료분리층에 대한 실험연구 (An Experimental Study of the Segregated Layers of Materials for Pretensioned Spun High Strength concrete Pile)

  • 이성로;강성수
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2000년도 봄 학술발표회 논문집
    • /
    • pp.148-152
    • /
    • 2000
  • The experimental study was performed to investigate the effects of centrifugal condition on the segregated layers of materials and the compressive strength of concrete for pretensioned spun high strength concrete (PHC) pile. The considering factors in the test were the centrifugal time and the magnitude of centrifugal force. These factors have been found to have found to have the great influence on the segregation and the concrete strength. The moderate centrifugal condition has to be fitted for the quality assurance in the production of PHC pile, especially to provide the adequate concrete cover over the tendons.

  • PDF

리모델링을 위한 기존 저층형 철근콘크리트의 안전성 평가 시스템 (Structural Safety Evaluation System of Existing low-rise Reinforced Concrete Buildings to Remodeling)

  • 김진수;김창은
    • 대한안전경영과학회지
    • /
    • 제5권3호
    • /
    • pp.69-80
    • /
    • 2003
  • This study researched problems of safety inspection method and current legislative system for the structure safety evaluation of Rahmen structure affected by remodeling. The elements of weight increase were examined in terms of differences of load moment, shear force, compressive stress and amount of steel before and after remodeling by structure analysis. The thorough examination for impacts of weight increase is indispensable to change of use or extension.

고성능 적층고무 면진장치의 요구 성능 (Demand Capacities of Rubber Bear ing for Seismic Isolated Building)

  • 황기태;임종만;김동원
    • 한국지진공학회:학술대회논문집
    • /
    • 한국지진공학회 2006년도 학술발표회 논문집
    • /
    • pp.487-494
    • /
    • 2006
  • The ultimate capacities of a rubber bearing are defined by compressive stress, shear strain, and stabilized roster ing force. The experiments were conducted with parameters of shesr elasticity(G) and first shape factor(S1), second shape factor(S2) for rubber bearing. Considering with test results, the ultimate capacities were verified, and furthermore the influence of those parameters were clarified. Using test results stable deformation of rubber bearings for designing was proposed.

  • PDF

탄소성 변형을 고려한 연속압연시 롤스탠드간 장력해석 (Calculation of Tensile Load between Roll Stands in Continuous Rolling System considering the Elasto-Plastic Behavior)

  • 신남도;손일헌;강경필;이경훈
    • 한국소성가공학회:학술대회논문집
    • /
    • 한국소성가공학회 2008년도 추계학술대회 논문집
    • /
    • pp.286-287
    • /
    • 2008
  • The determination of roll speeds in continuous rolling system is an important factor along with the design of roll profile and roll gap. The tensile force on the workpiece induces reduced cross section area and the compressive force induces wrinkles. To determine the optimal roll speeds of current rough rolling system for wire rod, FE analysis was performed. We could predict the workpiece shape and the stress level more precisely by considering the elasto-plastic behavior of workpiece. Also the efficient analysis methodology is presented to reduce the calculation time by combining the ALE and lagrangian method.

  • PDF

PRD 강환 말뚝의 연직지지력 특성에 관한 사례 연구 (Case Study on the Characteristics of Vertical Bearing Capacity for Steel Pipe Pile Installed by PRD)

  • 최용규;정창규;정성기;김동철;정태만
    • 한국지반공학회:학술대회논문집
    • /
    • 한국지반공학회 1999년도 봄 학술발표회 논문집
    • /
    • pp.225-232
    • /
    • 1999
  • Construction case of PRD (Percussion Rotary Drill) pipe pile and matters to be attended in construction of PRD pile were reviewed. The compressive and uplifting static pile load tests for PRD piles were performed and, also, analysis by Pile Driving Analyzer was done. Based on these results, bearing components in each resisting part (that is: steel toe, external skin, and internal skin) were measured separately. The measured resisting force was compared to the value calculated by the estimated formula. The pile capacity was mobilized in steel toe area and the external skin friction and the internal friction were not produced. Thus, it could be considered that toe of PRD pile should be supported in hard bearing stratum (for example, the fresh soft rock).

  • PDF

$SF_6$ 가스 안전밸브 디스크 시일의 최적설계에 관한 연구 (Shape Design Optimization of Disk Seal in $SF_6$ Gas Safety Valve)

  • 김청균;조승현
    • Tribology and Lubricants
    • /
    • 제20권5호
    • /
    • pp.231-236
    • /
    • 2004
  • Sulfur Hexafluoride, S $F_{6}$ is widely used for leak detection and as a gaseous dielectric in transformers, condensers and circuit breakers. S $F_{6}$ gas is also effective as a cleanser in the semiconductor industry. This paper presents a numerical study of the sealing force of disk type seal in S $F_{6}$ gas safety valve. The sealing force on the disk seal is analyzed by the FEM method based on the Taguch's experimental design technique. Disk seals in S $F_{6}$ gas safety valve are designed with 9 design models based on 3 different contact length, compressive ratio and gas pressure. The calculated results of Cauchy stress and strain showed that the sealing characteristics of Teflon $^{ }$PTFE is more effective compared to that of FKM(Viton), which is related to the stiffness of the materials. And also, the contact length of the disk seal is important design parameter for sealing the S $F_{6}$ gas leakage in the safety valve.afety valve.

철근콘크리트 원형단면 교각의 유효강성 (Effective Stiffness of Circular Reinforced Bridge Columns)

  • 배성용;김준범;이재훈
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2001년도 봄 학술발표회 논문집
    • /
    • pp.833-838
    • /
    • 2001
  • The objectives of this study are to investigate effective stiffness of circular reinforced bridge columns and to provide reasonable effective stiffness equations for seismic design to the current Korean Bridge Design Standard. The material nonlinear analysis was conducted for 5184 columns of which variables were the concrete compressive stress, the steel yielding stress, the longitudinal steel location parameter, the longitudinal steel ratio, the axial load level, and the diameter of section. The current Korean Bridge Design Standard generally used the gross section stiffness because of unclear provision, it may be non-conservative because of being evaluated greater design seismic force and less design displacement than those of the abroad provision. Therefore, the proposed effective stiffness equations include three variables such as : the longitudinal steel location parameter, the longitudinal steel ratio, and the axial load ratio. Two equations of effective stiffness are proposed which may be used for earthquake force estimation and for earthquake displacement estimation, respectively.

  • PDF

텐세그러티 구조의 외력에 대한 적정 프리스트레스 결정 (Optimal prestress of Tensegrity Structures for External Load)

  • 안정태;이재홍
    • 한국공간구조학회논문집
    • /
    • 제13권1호
    • /
    • pp.59-67
    • /
    • 2013
  • This paper presents a new numerical method to analyse tensegrity structures by using singular value decomposition and force method. The tensegrity system consisting of compressive and tensle elements are pin-jointed system. Tensegrity structures, unlike the general structure should be preceded by form-finding. Tensegrity structures form-finding of the self-equilibrium stress stability, seeking to have the process. In this study, tensegrity structures when subjected to external loads, find the optimal pre-stress values was studied.