• Title/Summary/Keyword: Computational Load

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Computational evaluation of wind loads on buildings: a review

  • Dagnew, Agerneh K.;Bitsuamlak, Girma T.
    • Wind and Structures
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    • v.16 no.6
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    • pp.629-660
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    • 2013
  • This paper reviews the current state-of-the-art in the numerical evaluation of wind loads on buildings. Important aspects of numerical modeling including (i) turbulence modeling, (ii) inflow boundary conditions, (iii) ground surface roughness, (iv) near wall treatments, and (vi) quantification of wind loads using the techniques of computational fluid dynamics (CFD) are summarized. Relative advantages of Large Eddy Simulation (LES) over Reynolds Averaged Navier-Stokes (RANS) and hybrid RANS-LES over LES are discussed based on physical realism and ease of application for wind load evaluation. Overall LES based simulations seem suitable for wind load evaluation. A need for computational wind load validations in comparison with experimental or field data is emphasized. A comparative study among numerical and experimental wind load evaluation on buildings demonstrated generally good agreements on the mean values, but more work is imperative for accurate peak design wind load evaluations. Particularly more research is needed on transient inlet boundaries and near wall modeling related issues.

Load Test and Remote Monitoring of P.C. Box Girder Bridge (P.C. BOX 교량의 재하시험 및 원격계측 유지관리 시스템)

  • Lee, Sung-Woo;Doobyong Bae;Lee, Sun-Goo
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1995.10a
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    • pp.122-131
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    • 1995
  • Load test for newly introduced precast segmental bridge is carried out to experimentally evaluate load carrying capacity, Analysis accompanied with the test is also performed and the results are used in the evaluation. In addition to initial evaluation of the bridge by load test, remote dynamic monitoring system to perform realtime assessment of the bridge condition is also under development. In this paper the procedure and results of load test and evaluation are presented along with introduction of dynamic monitoring system.

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Development of Train Load Model for Railway Bridge Time-History Analysis (철도교량의 동해석을 위한 하중모델의 개발)

  • 김현민;오지택
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2003.10a
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    • pp.97-102
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    • 2003
  • A real train load fluctuates along the track because of complicated movements(Bouncing, Rolling, Pitching and Yawing) and rail conditions. This research has for its object in development of a numerical real train load model including fluctuation characteristics of lateral forces. It is based on Klingel movement theory of a wheelset on straight track it presents a propriety of application by comparison between a 3D-Numerical analysis result using this train load model and a measured data. And this paper presents further study subject to improve a method about the train load modeling.

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Ultimate axial load of rectangular concrete-filled steel tubes using multiple ANN activation functions

  • Lemonis, Minas E.;Daramara, Angeliki G.;Georgiadou, Alexandra G.;Siorikis, Vassilis G.;Tsavdaridis, Konstantinos Daniel;Asteris, Panagiotis G.
    • Steel and Composite Structures
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    • v.42 no.4
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    • pp.459-475
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    • 2022
  • In this paper a model for the prediction of the ultimate axial compressive capacity of square and rectangular Concrete Filled Steel Tubes, based on an Artificial Neural Network modeling procedure is presented. The model is trained and tested using an experimental database, compiled for this reason from the literature that amounts to 1193 specimens, including long, thin-walled and high-strength ones. The proposed model was selected as the optimum from a plethora of alternatives, employing different activation functions in the context of Artificial Neural Network technique. The performance of the developed model was compared against existing methodologies from design codes and from proposals in the literature, employing several performance indices. It was found that the proposed model achieves remarkably improved predictions of the ultimate axial load.

Reliability-Based Dynamic Load Model for Bridges (교량 충격하중의 확률론적 모델)

  • 황의승
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1991.10a
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    • pp.69-72
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    • 1991
  • The purpose of this study is to develop the reliability-based dynamic load model for bridges. Analytial procedure to calculate the dynamic load is developed. Truck traffic is simulated using Monte Carlo method. Static and dynamic loads(deflections) are plotted on the normal probability paper to estimate the mean maximum dynamic load in bridge lifetime. The results may be served as a basis for new LRFD bridge design code.

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A study on the structural behaviors of air-pressurized vertical arch (공기로 지지되는 수직 아치의 구조거동에 관한 연구)

  • 김재열;이장복;권택진
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.10a
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    • pp.274-279
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    • 1998
  • The structural behaviors of a arch composed of flexible membrane are investigated. The membrane is considered as thin shell with internal pressure during FEM analysis by using ABAQUS. In the paper, a wind load and uniformly distributed vertical load are considered. As a vertical load, snow loads including applied over all and half of the structure are introduced. The ends of arch are fixed to the ground. Load-Deflections relationship, buckling mode of the structure are presented.

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A Study on Artificial Wheel Load Generation Method Using PSD Analysis (PSD 함수를 이용한 인공윤하중의 생성기법에 대한 연구)

  • Cho, Kwang-Il;Choi, Moon-Seock;Lim, Ji-Young;Kim, Sang-Hyo
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2008.04a
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    • pp.184-189
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    • 2008
  • In this study, an artificial wheel load generation method is proposed to assist practical engineers performing dynamic analysis with simple procedure. To generate an artificial wheel loads from running vehicle, PSD(Power Spectrum Density) profiles of actual wheel load were sampled in terms of various road roughnesses. A detailed truck and bridge models were used for sampling actual wheel load to represent the real motion of moving vehicle. These wheel load profiles were simplified for the artificial wheel load. The simplification of actual wheel load profiles was performed by regression analysis. The result showed that the artificial wheel load well represents the real profiles of wheel load.

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Computational load reduction by avoiding the recalculation of angular redundancy in computer-generated holograms

  • Jia, Jia;Chen, Jhensi;Chu, Daping
    • ETRI Journal
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    • v.41 no.1
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    • pp.52-60
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    • 2019
  • A fast hologram calculation approach is proposed to reduce computational load by avoiding the recalculation of redundancy information. In the proposed method, the hologram is divided into several sub-holograms that record and reconstruct different views of 3D objects. The sub-hologram is generated from its adjacent calculated sub-holograms by only adding the holograms of difference images between an adjacent pair of views. The repetitive information of two adjacent views is called angular redundancy. Therefore, avoiding the recalculation of this angular redundancy can considerably reduce the computational load. Experimental results confirm that the proposed method can reduce the computational time for the statue head, rabbits, and car to 4.73%, 6.67%, and 10.4%, respectively, for uniform intensity, and to 56.34%, 57.9%, and 66.24%, respectively, for 256 levels intensity, when compared to conventional methods.

Two-dimensional Chip-load Analysis for Automatic Feedrate Adjustment (이송률 자동조정을 위한 2차원 칩로드 해석)

  • 배석형;고기훈;최병규
    • Korean Journal of Computational Design and Engineering
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    • v.5 no.2
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    • pp.155-167
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    • 2000
  • To be presented is two-dimensional chip-load analysis for cutting-load smoothing which is needed in unmanned machining and high speed machining of sculptured surfaces. Cutter-engagement angle and effective cutting depth are defined as chip-loads which are the geometrical measures corresponding to cutting-load while machining. The extreme values of chip-loads are geometrically derived in the line-line and line-arc-line blocks of the two-dimensional NC-codes. AFA(automatic feedrate adjustment) strategy for cutting-load smoothing is presented based on the chip-load trajectories.

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