http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : Filip C. Filippou (검색결과 4 건)
- 무료
- 기관 내 무료
- 유료
-
Analysis of RC walls with a mixed formulation frame finite element
Afsin Saritas,Filip C. Filippou 사단법인 한국계산역학회 2013 Computers and Concrete, An International Journal Vol.12 No.4
This paper presents a mixed formulation frame element with the assumptions of the Timoshenko shear beam theory for displacement field and that accounts for interaction between shear and normal stress at material level. Nonlinear response of the element is obtained by integration of section response, which in turn is obtained by integration of material response. Satisfaction of transverse equilibrium equations at section includes the interaction between concrete and transverse reinforcing steel. A 3d plastic damage model is implemented to describe the hysteretic behavior of concrete. Comparisons with available experimental data on RC structural walls confirm the accuracy of proposed method.
-
Blast Analysis of RC Beams Based on Moment-Curvature Relationship Considering Fixed-End Rotation
Park, Gang-Kyu,Kwak, Hyo-Gyoung,Filippou, Filip C. American Society of Civil Engineers 2017 Journal of structural engineering Vol.143 No.9
<P>An improved numerical model that can simulate the nonlinear behavior of RC beams subjected to blast loadings is introduced in this paper. The model is based on the moment-curvature relationship of a RC section, and a dynamic increase factor (DIF) defined with the curvature rate is newly designed to be used in the moment-curvature relationship. The plastic hinge length is considered in the finite-element (FE) idealization of RC beams to accurately reflect the effects of the plastic deformation concentrated at the midspan or beam-column joint after yielding of the main reinforcement. A modification of the moment-curvature relationship is also proposed to take into account the fixed-end rotation accompanied by large bond-slip at the yielding stage of the main reinforcement. The advantages of the proposed model, compared with the layered-section approach, are reduced calculation time and memory space in application to large-frame structures with many degrees of freedom. Finally, correlation studies between analytical results and experimental studies are conducted to establish the validity of the proposed model, and the effect of the finite-element mesh size is also discussed in connection with the importance of considering the fixed-end rotation. The results are also compared with those obtained from the single-degree-of-freedom (SDOF) model to demonstrate the better prediction capability of the proposed method. (C) 2017 American Society of Civil Engineers.</P>
-
Park, Gang-Kyu,Kwak, Hyo-Gyoung,Filippou, Filip C. Elsevier 2018 Engineering failure analysis Vol.93 No.-
<P><B>Abstract</B></P> <P>A numerical method to estimate the dynamic response of reinforced concrete (RC) columns subjected to axial and blast loads is introduced in this paper. Upon adopting Timoshenko's beam theory, both the flexural and direct shear behaviors are incorporated into the numerical formulation. The moment-curvature relationship of a reinforced concrete (RC) section is based on the construction of the bending stiffness and, in advance, a dynamic increase factor (DIF), usually defined in the stress-strain relations of concrete and steel, is newly designed to be defined in the moment-curvature relation. In addition to the description of the dynamic characteristics in the RC section, additional modification of the moment-curvature relation is also performed to exactly simulate the large plastic deformation concentrated at the mid-span or beam-column joint due to the bond-slip or anchorage slip after yielding of the main reinforcement. Finally, the validity of the proposed method is verified by comparing the analytical results with the experimental data, and then the pressure-impulse (P–I) diagrams are constructed and compared to review the change in the resisting capacity of a RC column according to the variation of the axial force and slenderness ratio.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A numerical model incorporating the flexural behavior and the direct shear behavior is proposed. </LI> <LI> A dynamic increase factor (DIF) for the moment-curvature relationship is newly designed. </LI> <LI> The verification of the numerical model is performed through comparison with experimental data. </LI> <LI> A parametric study of RC column is performed to review the influence of the parameters. </LI> </UL> </P>
-
Thanh T. Banh,Xuan Q. Nguyen,Michael Herrmann,Filip C. Filippou,Dongkyu Lee 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.35 No.1
In typical, structural topology optimization plays a significant role to both increase stiffness and save mass of structures in the resulting design. This study contributes to a new numerical approach of topologically optimal design of Mindlin-Reissner plates considering Winkler foundation and mathematical formulations of multi-directional variable thickness of the plate by using multi-materials. While achieving optimal multi-material topologies of the plate with multi-directional variable thickness, the weight information of structures in terms of effective utilization of the material at the appropriate thickness location may be provided for engineers and designers of structures. Besides, numerical techniques of the well-established mixed interpolation of tensorial components 4 element (MITC4) is utilized to overcome a well-known shear locking problem occurring to thin plate models. The well-founded mathematical formulation of topology optimization problem with variable thickness Mindlin-Reissner plate structures by using multiple materials is derived in detail as one of main achievements of this article. Numerical examples verify that variable thickness Mindlin-Reissner plates on Winkler foundation have a significant effect on topologically optimal multi-material design results.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
