• 제목/요약/키워드: quasi static analysis

검색결과 415건 처리시간 0.029초

A quasi-static finite element approach for seismic analysis of tunnels considering tunnel excavation and P-waves

  • Zhao, Wusheng;Zhong, Kun;Chen, Weizhong;Xie, Peiyao
    • Earthquakes and Structures
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    • 제22권6호
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    • pp.549-559
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    • 2022
  • The quasi-static finite element (FE) approaches are widely used for the seismic analysis of tunnels. However, the conventional quasi-static approaches may cause significant deviations when the tunnel excavation process is simulated prior to the quasi-static analysis. In addition, they cannot account for vertical excitations. Therefore, this paper first highlights the limitations of conventional approaches. A hybrid quasi-static FE approach is subsequently proposed and extensively validated for various conditions. The hybrid approach is simple and not time consuming, and it can be used for the preliminary seismic design of tunnels, especially when the tunnel excavation and vertically propagating P-waves are considered.

Strength and stiffness of cold-formed steel portal frame joints using quasi-static finite element analysis

  • Mohammadjani, Chia;Yousefi, Amir M.;Cai, Shu Qing;Clifton, G. Charles;Lim, James B.P.
    • Steel and Composite Structures
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    • 제25권6호
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    • pp.727-734
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    • 2017
  • This paper describes a quasi-static finite element analysis, which uses the explicit integration method, of the apex joint of a cold-formed steel portal frame. Such cold-formed steel joints are semi-rigid as a result of bolt-hole elongation. Furthermore, the channel-sections that are being connected have a reduced moment capacity as a result of a bimoment. In the finite element model described, the bolt-holes and bolt shanks are all physically modelled, with contact defined between them. The force-displacement curves obtained from the quasi-static analysis are shown to be similar to those of the experimental test results, both in terms of stiffness as well as failure load. It is demonstrated that quasi-static finite element analysis can be used to predict the behavior of cold-formed steel portal frame joints and overcome convergence issues experienced in static finite element analysis.

열차 진입 시 풍압에 의한 완전 밀폐형 승강장 스크린 도어(PSD)시스템의 구조 안정성 평가 (Evaluation of the Structural Stability of Platform Screen Door (PSD) due to Train Wind Pressure)

  • 이재열;류봉조;김동현;이은규;신광복
    • 한국철도학회논문집
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    • 제9권5호
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    • pp.594-600
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    • 2006
  • In this study, transient and quasi-static analysis were done for the evaluation of structural integrity of the platform screen door due to train wind pressure. Fluent 6.0 was used to calculate the train wind pressure, and Ansys 10.0 was used to evaluate the structural stability of platform screen door due to train wind pressure. Transient analysis was used to check the design requirements of platform screen door, and quasi-static analysis was introduced to save the calculating time and check quickly structural performances when compared to those of transient analysis. The results show that structural stability of the platform screen door under train wind pressure is proven and quasi-static analysis can quickly check the structural integrity of platform screen door.

실시간 다물체 차량 해석을 위한 준정적법의 컴플라이언스 효과 모델링 (Compliance Effect Modeling based on Quasi-static Analysis for Real-time Multibody Vehicle Dynamics)

  • 정완희;하경남;김성수
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회A
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    • pp.1003-1008
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    • 2007
  • Compliance effect consideration method for real-time multibody vehicle dynamics is proposed using quasi-static analysis. The multibody vehicle model without bush elements is used based on the subsystem synthesis method which provides real-time computation on the multibody vehicle model. Reaction forces are computed in the suspension subsystem. According to deformation from the quasi-static analysis using reaction forces and bush stiffness, suspension hardpoint locations and suspension linkage orientation are changed. To validate the proposed method, quarter car simulations of McPherson strut and multilink suspension subsystems. Full car bump run simulations are also carried out comparing with the ADAMS vehicle model with bush elements. CPU times are also measured to see the real-time capabilities of the proposed method.

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실시간 다물체 차량 해석을 위한 준정적법의 컴플라이언스 효과 모델링 (Compliance Effect Modeling Based on Quasi-Static Analysis for Real-Time Multibody Vehicle Dynamics)

  • 김성수;정완희;하경남
    • 대한기계학회논문집A
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    • 제32권2호
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    • pp.162-169
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    • 2008
  • Compliance effect consideration method for real-time multibody vehicle dynamics is proposed using quasi-static analysis. The multibody vehicle model without bush elements is used based on the subsystem synthesis method which provides real-time computation on the multibody vehicle model. Reaction forces are computed in the suspension subsystem. According to deformation from the quasi-static analysis using reaction forces and bush stiffness, suspension hardpoint locations and suspension linkage orientation are changed. To validate the proposed method, quarter car simulations of McPherson strut and multilink suspension subsystems are performed. Full car bump run simulations and fish hook handling test simulations are also carried out comparing with the ADAMS vehicle model with bush elements. CPU times are also measured to see the real-time capabilities of the proposed method.

분산 분석을 이용한 자동차 안전벨트 준정적 해석과 인장시험 상관성 개선 (Quasi-static Analysis of Vehicle Seatbelt Using Analysis of Variance and Improvement of Tensile Test Correlation)

  • 이광섭;어영우;김삼성;김두용;송택림;이경상
    • 한국자동차공학회논문집
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    • 제24권3호
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    • pp.273-278
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    • 2016
  • This study makes a relative comparison of the results of tensile test and quasi-static analysis using AGL(Adjuster Guide Loop) model that plays a role in adjusting the height of shoulder belt, of the components of the vehicle seatbelt system and attempts to propose a method of reducing the error rate of the quasi-static analysis technique effectively. This study selects two major factors affecting the result of an analysis, draws the result of analysis through the method of experimental design, one of the statistical techniques and understands the contribution rate of the major factors affecting the result of the analysis through ANOVA(Analysis of Variance).

Quasi-static Analysis on the Effect of the Finite Metal with the Anisotropic Grooved Dielectric in Microstrip Lines

  • Hong Ic-Pyo
    • 마이크로전자및패키징학회지
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    • 제12권1호
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    • pp.17-20
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    • 2005
  • In this paper, we presented the quasi-static characteristics of novel microstrip lines with anisotropic grooved dielectric in finite metal. A quasi-static mode-matching method has been used to analyze this new structure and the simulation results are validated through comparison with other available results. The results in this paper show that it is possible to control the propagation characteristics of microstrip lines with the use of anisotropic grooved dielectric in finite metal. Also anisotropic grooved dielectric in microstrip line can be newly added to the design parameters of high performance three dimensional monolithic microwave circuits and other microwave applications.

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Influence of shear deformation of exterior beam-column joints on the quasi-static behavior of RC framed structures

  • Costa, Ricardo J.T.;Gomes, Fernando C.T.;Providencia, Paulo M.M.P.;Dias, Alfredo M.P.G.
    • Computers and Concrete
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    • 제12권4호
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    • pp.393-411
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    • 2013
  • In the analysis and design of reinforced concrete frames beam-column joints are sometimes assumed as rigid. This simplifying assumption can be unsafe because it is likely to affect the distributions of internal forces and moments, reduce drift and increase the overall load-carrying capacity of the frame. This study is concerned with the relevance of shear deformation of beam-column joints, in particular of exterior ones, on the quasi-static behavior of regular reinforced concrete sway frames. The included parametric studies of a simple sub-frame model reveal that the quasi-static monotonic behavior of unbraced regular reinforced concrete frames is prone to be significantly affected by the deformation of beam-column joints.

The mixed finite element for quasi-static and dynamic analysis of viscoelastic circular beams

  • Kadioglu, Fethi;Akoz, A. Yalcin
    • Structural Engineering and Mechanics
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    • 제15권6호
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    • pp.735-752
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    • 2003
  • The quasi-static and dynamic responses of a linear viscoelastic circular beam on Winkler foundation are studied numerically by using the mixed finite element method in transformed Laplace-Carson space. This element VCR12 has 12 independent variables. The solution is obtained in transformed space and Schapery, Dubner, Durbin and Maximum Degree of Precision (MDOP) transform techniques are employed for numerical inversion. The performance of the method is presented by several quasi-static and dynamic example problems.