• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.1109-1114
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• 2001

This paper describes an attempt to develop a new truss model for reinforced concrete beams failing in shear based on a rational behavioral model. The key idea incorporated with truss model is the internal force state factor which is able to express global state of internal force flow in cracked reinforced concrete beams subjected to shear and bending. A new truss model using internal force state factor may provide a comprehensive result of shear strength in reinforced concrete beams without web reinforcement.

• 한국구조물진단유지관리공학회 논문집
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• 제18권6호
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• pp.97-104
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• 2014

중공슬래브는 슬래브의 자중을 감소시킴으로써 콘크리트 하중을 제어하여 수직 구조 부재 하중 및 지진 하중의 양을 감소시키는 바닥구조시스템이다. 중공슬래브는 슬래브의 자중을 획기적으로 줄일 수 있지만 슬래브 내부의 중공부로 인하여 휨 및 전단강도가 감소하기 때문에 구조 성능의 예측이 매우 중요하다. 중공슬래브에 관한 국내외의 많은 연구에도 불구하고 일방향 중공슬래브의 전단보강에 따른 전단강도에 관한 연구는 많이 이루어지지 않고 있다. 따라서 본 연구에서는 전단보강 유무에 따른 일방향 중공슬래브의 파괴양상 분석과 산정식의 전단강도와 실험값의 전단강도의 비교를 통하여 일방향 중공슬래브의 전단보강의 필요성에 대해 검증하고자 한다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.597-602
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• 2001

Most of the predicted shear strength of continuous R.C. beam whitout web reinforcement were accepted by testing simple beams. But the experimental results may show that a differential behavior on simple and continuous R.C. beam. In this study, estimated shear strength of continuous R.C. beam without web reinforcement with internal force state factors by test as purpose to apply available predicted equation to normal continuous R.C. beam. This equation is applied to experimentally tested data and the results were compared with those predicted by the codes. Predicted shear strength using force state factor can provide a tested data rather than codes which like ACI

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 봄 학술발표회 논문집
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• pp.609-614
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• 2001

This paper is to explain reasonable shear behavior that can apply usually to reinforced concrete beams on the basic concepts of existent analysis and experimental research information. This study is succession $paper^{2) 3) 4) 5)}$ of treatise announced in existing and main control variable of reinforced concrete beams with stirrups used internal force state factor($\alpha$). Shear failure of reinforced concrete beams with stirrups is Influenced greatly because of the actual geometrical shape(a/d) of the concrete and flexural reinforcement steel ratio, stirrup reinforcement ratio and concrete compression strength, size effect etc. Therefore, shear behavior of reinforced concrete beams with stirrups that flexural crack is happened can be explained easily through proper extent proposal of internal force state factor($\alpha$) that express internal force state flowing. Use existent variable truss model by analysis model to explain arch action. Also, wish to compose each failure factors and correlation with internal force state factor by function, and when diagonal cracks happens, internal force state factor($\alpha$) study whether shear stress and some effect are.

• Steel and Composite Structures
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• 제33권3호
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• pp.463-472
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• 2019

Initial thermo-elastic and steady state creep deformation of a rotating functionally graded simple blade is studied using first-order shear deformation theory. A variable thickness model for cantilever beam has been considered. The blade geometry and loading are defined as functions of length so that one can define his own blade profile and loading using any arbitrary function. The blade is subjected to a transverse distributed load, an inertia body force due to rotation and a distributed temperature field due to a thermal gradient between the tip and the root. All mechanical and thermal properties except Poisson's ratio are assumed to be longitudinally variable based on the volume fraction of reinforcement. The creep behaviour is modelled by Norton's law. Considering creep strains in stress strain relation, Prandtl-Reuss relations, Norton' law and effective stress relation differential equation in term of effective creep strain is established. This differential equation is solved numerically. By effective creep strain, steady state stresses and deflections are obtained. It is concluded that reinforcement particle size and form of distribution of reinforcement has significant effect on the steady state creep behavior of the blade.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.873-878
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• 2001

This Paper Presents a new model, called the “shear-friction truss model,” for slender reinforced concrete beams to derive a clear and simple equation for their ultimate shear strength. In this model, a portion of the shear strength is provided by shear reinforcement as in the traditional truss model, and the remainder by the shear-friction mechanism. Friction resistance is derived considering both geometrical configuration of the rough crack surface and material Properties. The inclined angle of diagonal strut in the traditional truss model is modified to satisfy the state of balanced failure, when both stirrups and longitudinal reinforcement yield simultaneously. The vertical component of friction resistance is added to the modified truss model to form the shear-friction truss model. Test results from published literatures are used to find the effective coefficient of concrete strength in resisting shear on inclined crack surfaces.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(I)
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• pp.407-410
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• 2005

This paper describes an evaluation of reinforcement tension in RC beams using the variable truss models. The models were examined with the beam test results by Kim, Kim and White. Consequently, a fixed inclination $\theta$ at the support un-explains global state of internal force flow in cracked reinforced concrete beams subjected to shear and bending. Accordingly, we must introduce the arch factor for development of consistent model in reinforced concrete beams subjected to shear and bending

• 한국전산구조공학회논문집
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• 제16권1호
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• pp.43-52
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• 2003

본 논문은 콘크리트 균열방향의 회전 및 철근의 항복에 따른 2차원 R/C 구조물의 극한거동 덴 한계상태설계에 관한 연구를 다룬 것으로, 유한요소모델에 적용하여 비선형 해석 및 한계상태설계가 가능한 수치 해석 및 설계 알고리즘을 소개하였다. 철근의 설계를 위하여, 각 유한요소의 극한거동에 기초한 한계상태설계방정식이 유한요소 알고리즘에 도입되었다. 한편, 하중에 따른 콘크리트 균열방향의 회전 및 철근의 항복을 고려한 2차원 R/C 평면요소의 단순화된 실용적 비선형 응력-변형률 거동의 구성관계모델을 제시하여 비선형 유한요소해석 알고리즘을 구성하였다 제시된 해석 모델을 R/C 전단벽의 실험모델과 비교하여 검증하도록 하였으며, R/C 전단벽에 대한 설계 예를 통하여, 각각의 유한요소에서 얻어진 설계 철근비를 한계상태설계방정식으로부터 산정하였다.

• Journal of Advanced Research in Ocean Engineering
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• 제1권1호
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• pp.1-13
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• 2015

Post-Katrina investigations revealed that most earthen levee damage occurred on the levee crest and landward-side slope as a result of either wave overtopping, storm surge overflow, or a combination of both. In this paper, combined wave overtopping and storm surge overflow of a levee embankment strengthened with high performance turf reinforcement mat (HPTRM) system was studied in a purely Lagrangian and meshless approach, two-dimensional smoothed particle hydrodynamics (SPH) model. After the SPH model is calibrated with full-scale overtopping test results, the overtopping discharge, flow thickness, flow velocity, average overtopping velocity, shear stress, and soil erosion rate are calculated. New equations are developed for average overtopping discharge. The shear stresses on landward-side slope are calculated and the characteristics of soil loss are given. Equations are also provided to estimate soil loss rate. The range of the application of these equations is discussed.

• 한국구조물진단유지관리공학회 논문집
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• 제5권1호
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• pp.195-205
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• 2001

An analytical finite element approach to nonlinear behavior of reinforced concrete shear walls with opening under monotonic loading was presented in this paper. In order to achieve the objectives of present paper, the orthogonal anisotropic models for cracked reinforced concrete element based on smeared crack concept were used as the nonlinear material models of biaxial state of stress. The stiffness of cracked concrete was evaluated through the combined use of tension and compression stiffness models in and parallel directions of crack, respectively and shear transfer effect due to the aggregate interlocking at crack surface. The stress and strain of reinforcement in concrete was evaluated using the average stress and average strain relation with bond effect. based on smeared crack concept. The diagonal reinforcing bar was modeled using truss element with bond effect. A special significance of diagonal reinforcement near opening was given to the shear wall with opening and an effective distribution of diagonal reinforcement was presented in order to give an ultimate strength increment as well as a crack control.