• Computers and Concrete
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• 제8권1호
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• pp.59-70
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• 2011

A theoretical model known as the modified rotating-angle softened-truss model (MRA-STM), which is a modification of Rotating-Angle Softened-Truss Model and Modified Compression Field Theory, is presented for the analysis of reinforced concrete membranes in shear. As an application, shear strength and behaviour of reinforced concrete exterior beam-column joints are analysed using the MRA-STM combining with the deep beam analogy. The joints are considered as RC panels and subjected to vertical and horizontal shear stresses from adjacent columns and beams. The strut and truss actions in a beam-column joint are represented by the effective transverse compression stresses and a softened concrete truss in the proposed model. The theoretical predictions of shear strength of reinforced concrete exterior beam-column joints from the proposed model show good agreement with the experimental results.

• 한국산업융합학회 논문집
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• 제21권2호
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• pp.53-62
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• 2018

This study propose a new approach to control the optimal working path of vertical type articulated robot with translation joint for trimming working process automation in forging manufacturing process. The basic structure of the proposed robotic joints controller consists of a Proportional-Intergral controller and a Proportional-Derivative controller in parallel. The proposed control scheme takes advantage of the properties of the fuzzy PID controllers. The proposed method is suitable to control of the trajectory and path control in cartesian space for vertical type articulated robot manipulator. The results illustrates that the proposed fuzzy computed torque controller is more stable and robust than the conventional computed torque controller. The reliability is varified by simulation test for vertical type s articulated robot with seven joints including one trqanslation joint.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.814-819
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• 2003

Machine tool design concepts have evolved towards high efficiency, accurate precision. high structural integrity, and multi-functional systems. Like many other structures, machine tools are also composed of many parts. When these parts are assembled, many kinds of joints are used. In the finite element analysis of these assembled structures, most joints are commonly considered as rigid joints. But, to get the more accurate solution, we need to model these joints in a appropriate manner. In this study, rational dynamic modeling and analysis method for complex structures are studied with special attention to slide way joints. For modeling of slide way joints, a general modeling technique is used by influence coefficients method which is applied to the conversion of detailed finite element model to the equivalent reduced joint model. The theoretical part of this method is illustrated and the method is applied to the structure with slide way joint. In this method. the non-linearity of the contact surfaces is considered within a proper range and the boundary effect of the joint model can be eliminated. The proposed method was applied to finite element modal analysis of a clamp jointed cantilever beam and slide way joints of the vertical type lathe. The method can also be used to other kinds of joint modeling. The results of these analysis were compared with those of Yoshimura models and rigid joint models. which demonstrated the practical applicability of the proposed method.

• 콘크리트학회지
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• 제8권4호
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• pp.171-179
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• 1996

PC판넬 조립식 구조의 수직.수평접합부의 유용한 접합형태에 따라 접합부 전단내력을 상승시킬 수 있는 접합부 설계의 기본 형태를 제시하는데 연구의 목적이 있다. 시험체는 수직접합부의 경우 전단키의 개수 및 보강철물의 종류에 변수를 주고 수평접합부의 경우에는 전단키의 갯수 및 가력방향에 변수를 주어 총 22개의 시험체를 제작하여 실험하였다. 결론적으로 수직접합부의 경우, 수평보강철물이 있는 시험체는 기존의 다른 실험결과와 마찬가지로 수평보강철물이 없는 시험체에 비하여 연성이 크게 나타났다. EH한 와이어로프와 원형철근 두 종류의 보강철물을 사용하여 실험한 결과 와이어 로프를 사용한 시험체는 원형철근을 사용한 시험체와 최대내력 및 전단강성 등 전체적인 구조거동이 거의 비슷하게 나타났다.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.395-396
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• 2023

The current building structural standards present design requirements for the vertical construction joint of a slurry wall when it is used as a permanent wall. This paper proposes design methods and considerations according to the requirements of the relevant standards.

• 한국운동역학회지
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• 제13권2호
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• pp.49-63
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• 2003

For this study, four male university Taekwondo players were randomly chosen, between the weight categories of 60Kg and 80Kg. Their side kicks (yeop chagi), which are part of foot techniques, were kinematically analyzed in terms of the time, angle, and angular velocity factors involved with the kicks through the three-dimensional imaging. The results of the analysis are as fellows. 1. Time factor The first phase(preparation) was 0.48sec on average, accounting for 60% of the entire time spent; the second phase(the minimum angle of the knee joint) was 0.21sec on average, taking up 26% of the whole time spent; and the third phase(hitting) was 0.11sec on average, representing 14% of the entire time spent. 2. Angle factor In the first phase(preparation), rotating their bodies along the long axis, the players bended their hip and knee joints a lot, by moving fast in the vertical and horizontal directions, in the second phase(the minimum angle of the knee joint), the players continued to extend their bodies along the vertical axis, while pronating their lower legs and bending their hip and knee joints a lot to reduce the radius of gyration, and in the third phase(hitting), they extended their knee joints greatly so that the angle movements of their lower bodies shifted to circle movements. 3. Angular velocity factor In the first phase(preparation), the angular velocity of the hip and knee joints increased. while moving horizontally and rotating the body along the long axis; in the second phase(the minimum angle of the knee joint), the angular velocity increased by bending the hip and knee joints fast to reduce the rotation radios; and in the third phase(hitting), the angular velocity was found to have increased, by rotating the body along the long axis to increase the angular velocity and shifting the angular momentum of the pronated knee joint to the circular momentum.

• 한국산학기술학회논문지
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• 제17권1호
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• pp.298-303
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• 2016

수직 및 수평의 원형단면 강관으로 구성된 공간프레임 타워는 강재량을 줄이면서도 풍하중의 영향을 완화시킬 수 있는 장점으로 다양한 목적으로 널리 적용되고 있다. 이러한 공간프레임 타워를 하나의 타워구조로 거동하게 하기 위해서는 수직 강관과 수평 강관의 연결부인 강관조인트의 강도 확보가 중요하다. 본 연구에서는 압축과 휨이 동시에 작용하는 강관 T조인트의 강도평가를 수행하였다. AISC, Eurocode3, ISO 19902의 3가지 강관조인트 설계기준을 검토하고, 주강관과 지강관의 세장비를 주요 매개변수로 한 비선형 유한요소해석을 통하여 축력과 모멘트에 대한 극한강도 상호작용을 설계식으로 제안하였다.

• 한국정밀공학회지
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• 제23권6호
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• pp.128-135
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• 2006

Rational dynamic modeling and analysis method f3r complex structures are studied with special attention to slide way joints. For modeling of slide way joints, a general modeling technique is used by using the influence coefficients method which is applied to the conversion of detailed finite element model to the equivalent reduced joint model. The theoretical part of this method is illustrated and the method is applied to the structure with slide way joint. In this method, the non-linearity of the contact surfaces is considered within a proper range and the boundary effect of the joint model could be eliminated. The proposed method was applied to finite element modal analysis of a clamp jointed cantilever beam and slide way joints of the vertical type lathe. The method can also be used to other kinds of joint modeling. The results of these analysis were compared with those of Yoshimura models and rigid joint models, which demonstrated the practical applicability of the proposed method.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1994년도 가을 학술발표회 논문집
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• pp.362-367
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• 1994

In Precast Concrete Structure, safety of structure depends on strength of joint. Asa result, there exists a necessity to review the effects of elements consisting joints, since these elements are important factors for evalaution of joint strength. However, there elements are different for construction methods and may be changed even during construction. Obviously, the change of elements can cause the change of joint strength; yet, the effects of the variables are not clearly defined. The behavior of the joints are complicated and evaluated only through experiments. Consequently, the main objective of this paper is to review effects of components consisting Precast Joints, I order to keep higher joint strength than specified in the design code.

• Structural Engineering and Mechanics
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• 제62권5호
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• pp.643-649
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• 2017

Masonry walls are amongst the oldest building systems. A large portion of the research on these structures focuses on the load-bearing walls. Numerical methods have been generally used in modelling load-bearing walls during recent years. In this context, macro and micro modelling techniques emerge as widely accepted techniques. Micro modelling is used to investigate the local behaviour of load-bearing walls in detail whereas macro modelling is used to investigate the general behaviour of masonry buildings. The main objective of this study is to investigate the elastic behaviour of the load- bearing walls in masonry buildings by using micro modelling technique. In order to do this the brick and mortar units of the masonry walls are modelled by the combination of plane truss elements and plane frame elements with no shear deformations. The model used in this study has fewer unknowns then the models encountered in the references. In this study the vertical frame elements have equivalent elasticity modulus and moment of inertia which are calculated by the developed software. Under in-plane static loads the elastic displacements of the masonry walls, which are encountered in literature, are calculated by the developed software, where brick units are modelled by plane frame elements, horizontal joints are modelled by vertical frame elements and vertical joints are modelled by horizontal plane truss elements. The calculated results are compatible with those given in the references.