• Title/Summary/Keyword: Stiffness curve

Search Result 377, Processing Time 0.03 seconds

A study on the parameters to ensure safety against derailment (탈선 안전성능 향상을 위한 매개변수에 관한 연구)

  • Hwang, Jeong-Taek;Lee, Hi-Sung;Mok, Jin-Yong
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2007.05a
    • /
    • pp.297-303
    • /
    • 2007
  • Derailment is likely to have a direct connection with human life and must be eliminated. A traveling safety evaluation method based mainly on derailment coefficient has already established. But this method is very difficult because Derailment is caused by multiple factors. To evaluate the derailment factor of running train that runs on the curved track, we make use of mechanism that wheel loads and lateral forces were affected by track and rolling stock parameter. In this paper, deal with a search on the parameter and derailment factor. According to results of computer simulation value of Q/P, running safety is connected with operation velocity, curve radius, cant, track irregularity, suspension stiffness and static wheel load ratio, SMRT train Line No. 5 Bogie is selected to do numerical study considering rolling stock and track condition.

  • PDF

A Study on Fine Element Modeling Method of Yaw Bearing for Wind Turbine (풍력터빈 요 베어링의 유한요소모델링 기법에 관한 연구)

  • Seok, Ho-Il;Ko, Woo-Shick;Choi, Won-Ho;Lee, Seung-Kuh
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2006.11a
    • /
    • pp.249-252
    • /
    • 2006
  • Recently, the interest for renewable energy producing system is increasing rapidly. Among these, the wind turbine is most highlighted. It is installed at severe environment and generate electricity for a long time to exceed in 20. Components of wind turbine are required high reliability. Therefore, structural strength analysis for wind turbine is needed an accurate FE model. This paper is to provide reliable fine element modeling method of yaw bearing for wind turbine.

  • PDF

Experimental study on seismic performances of steel framebent structures

  • Liang, Jiongfeng;Gu, Lian S.;Hu, Ming H.
    • Earthquakes and Structures
    • /
    • v.10 no.5
    • /
    • pp.1111-1123
    • /
    • 2016
  • To study seismic performance of steel frame-bent structure, one specimen with one-tenth scale, three-bay, and five-story was tested under reversed cyclic lateral load. The entire loading process and failure mode were observed, and the seismic performance indexes including hysteretic loops, skeleton curve, ductility, load bearing capacity, drift ratio, energy dissipation capacity and stiffness degradation were analyzed. The results show that the steel frame-bent structure has good seismic performance. And the ductility and the energy dissipation capacity were good, the hysteresis loops were in spindle shape, which shape were full and had larger area. The ultimate elastic-plastic drift ratio is larger than the limit value specified by seismic code, showing the high capacity of collapse resistance. It can be helpful to design this kind of structure in high-risk seismic zone.

Self compacting reinforced concrete beams strengthened with natural fiber under cyclic loading

  • Prasad, M.L.V;saha, Prasenjit;Kumar, P.R.
    • Computers and Concrete
    • /
    • v.17 no.5
    • /
    • pp.597-612
    • /
    • 2016
  • The present work focuses on the use of coconut fiber in self compacting concrete. Self-Compacting Concrete (SCC) is a highly flowable, stable concrete which flows readily into place, filling formwork without any consolidation and without undergoing any significant segregation. Use of fibers in SCC bridge the cracks and enhance the performance of concrete by not allowing cracks to propagate. They contribute to an increased energy absorption compared to plain concrete. Coconut fiber has the highest toughness among all natural fibers. It is known that structures in the seismic prone areas are always under the influence of cyclic loading. To justify the importance of strengthening SCC beams with coir fiber, the present work has been undertaken. A comparison is made between cyclic and static loading of coconut fiber reinforced self compacting concrete (FRSCC) members. Using the test data obtained from the experiment, hysteresis loops were drawn and comparison of envelope curve, energy dissipation, stiffness degradation were made and important conclusions were draw to justify the use of coconut fiber in SCC.

A Discrete Analysis of Dynamic Plastic Response of Beam-Columns (Beam-Column의 동적(動的) 역성(逆性) 응답(應答)에 관한 이산화(離散化) 해석(解析))

  • Sung-Hwan,Park;Chang-Doo,Jang
    • Bulletin of the Society of Naval Architects of Korea
    • /
    • v.24 no.3
    • /
    • pp.43-51
    • /
    • 1987
  • In this paper, dynamic elastic, plastic response of beam-columns is analysed using discrete models. composed of rigid bars and springs. The equation of motion is formulated including the shear deformation effect, and the stress change of yielding points is calculated with various yielding criteria. The effect of initial axial force is considered by two ways: (1) including the effect in interaction curve only. (2) including the effect directly in the equation of motion in terms of initial stiffness method is also used in nonlinear interaction procedure. It is found that this model is very effective in analysing not only the plastic response but the elastic response, and present method is more efficient than Finite Element Method from the viewpoint of calculation time and accuracy.

  • PDF

Field Test on Rigidities of Piers in High-speed Railway (고속전철 교각의 강성도 산정을 위한 현장실험)

  • 진원종;곽종원;김병석;박성용
    • Proceedings of the Korea Concrete Institute Conference
    • /
    • 2000.10a
    • /
    • pp.745-750
    • /
    • 2000
  • The rigidity of pier is important in the analysis of rail on high speed railway bridges. This study is being performed because of followings. 1) Actual longitudinal stiffness of the structure including substructure should be considered in the calculation of longitudinal stresses in rails. 2) There are many uncertainties in piers and foundations for design. 3) Actual guideline for the design of piers is necessary. 4) Measurement on the rigidity of pier according to the types of pier, foundation and soil-condition is needed. Curve for rigidity will be obtained through this study and applied for actual design as the guideline. Stresses in rails can be estimates accurately. A pair of piers, which consists of pot-bearing for fixed support and pad-bearing for movable support, is loaded by steel frame through steel wire ropes. The responses which are intended to measure in the field test are displacements, forces and tilts on the top of piers.

  • PDF

Load Transfer Characteristics of Rock-Socketed Drilled Shafts Considering Hole Roughness (굴착면 거칠기를 고려한 암반 근입 현장타설말뚝의 주면하중전이 특성)

  • Seol, Hoon-Il;Jeong, Sang-Seom;Woo, Sang-Yoon
    • Proceedings of the Korean Geotechical Society Conference
    • /
    • 2006.03a
    • /
    • pp.494-505
    • /
    • 2006
  • In this study, using constant normal stiffness(CNS) direct shear tests, side shear load distribution were analyzed by the influencing parameters of unconfined compressive strength, surface roughness, confining stress, and material properties. Based on the CNS tests, side shear load transfer function of drilled shafts in rock is proposed using geological strength index(GSI), which indicates discontinuity and surface condition of rock mass in Hoek-Brown criterion. Though comparisons with results of nine drilled shafts's load tests, it is found that the load-transfer curve by this study is in good agreement with the general trend observed by in situ measurements, and thus represents a significant improvement in the prediction of bearing capacity of drilled shaft.

  • PDF

Cyclic behaviour of end-plate beam-to-column composite joints

  • Simoes, Rui;da Silva, Luis Simoes;Cruz, Paulo J.S.
    • Steel and Composite Structures
    • /
    • v.1 no.3
    • /
    • pp.355-376
    • /
    • 2001
  • An experimental research program on end-plate beam-to-column composite joints under cyclic loading is presented. The major focus relates to the identification of the contribution of the concrete confinement in composite columns to the behaviour of the joint, on internal nodes and external nodes, together with an assessment of degradation of strength and stiffness in successive loading cycles. From the experimental results it was possible to identify the various failure modes and to fit the corresponding hysteretic curves to the Richard-Abbott and Mazzolani models. These curve-fitting exercises highlighted the need to adapt both models, either for improved ease of application, or to deal with some aspects previously not covered by those models.

Cyclic performance of concrete beams reinforced with CFRP prestressed prisms

  • Liang, Jiongfeng;Deng, Yu;Hu, Minghua;Tang, Dilian
    • Computers and Concrete
    • /
    • v.19 no.3
    • /
    • pp.227-232
    • /
    • 2017
  • This paper describes an experimental study of the cyclic performance of concrete beams reinforced with CFRP prestressed concrete prisms (PCP). The failure modes, hysteretic loops, skeleton curve, ductility, energy dissipation capacity and stiffness degradation of concrete beams reinforced with CFRP prestressed concrete prisms were analyzed. The results show that The CFRP prestressed prisms reinforced concrete beams have good seismic performance. The level of effective prestress and cross section of CFRP prestressed prisms had a little influence on the bearing capacity, the ductility and energy dissipation capacity of CFRP prestressed prisms reinforced concrete beams.

Shear performance of green timber wall panels (그린팀버월 패널의 전단성능)

  • Kim, Yun-Hui;Shin, Il-Joong;Jang, Sang-Sik
    • Korean Journal of Agricultural Science
    • /
    • v.38 no.3
    • /
    • pp.541-547
    • /
    • 2011
  • Korean building industry was developed by concrete and steel construction. However, concrete and steel have some problems which low carbon storage capability and difficulty of recycling. According to many studies, timber has high carbon storage capability, high recycling capability and sustainable supporting capability. Focus on this factors of timber, make new wall structure as Green Timber Wall panels and check the shear performance to use wall system in housing construction such as light-weight timber construction and nondearing wall on other construction. In the results, B-4-B and B-4-S show similar modulus of shear stiffness on the table. GH-4-GH has slip shape failure mode between Green Timber Wall boards. GH-4-GV has most stable characteristic curve than other specimens.