• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.940-944
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• 2004

This is a thesis about the Solid Coupling Design and Torsional Angular Error Character. The solid coupling which is designed and made is a strong rigidity material. This is a experiment of Solid Coupling Torsional Error. The Angular Error, FEM and Circularity Measurement. Devices are Twist Friction Driver, Polygon, Autocollimator and Standard Encoder for Measurement. Coupling caused by elastic deformation causes angular error.

• Coupled systems mechanics
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• 제4권3호
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• pp.237-249
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• 2015

In the gear meshing process, gear temperature field concerns the meshing surface friction, the friction heat depends on the contact pressure, the contact pressure is affected by the elastic deformation of gears and the temperature field caused by the thermal deformation, so the temperature field, stress field and displacement field should be mutual coupling. It is necessary to consider in meshing gear pair in the operation process of thermodynamic coupling contact stress (TCCS) and thermodynamic coupling deformation (TCD), and based on thermodynamic coupling analysis (TCA) of gear teeth deformation.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 추계 학술발표회 제17권2호
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• pp.53-56
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• 2005

This paper investigates the effect of ductile deformation behavior of high performance hybrid fiber-reinforced cement composites (HPHFRCCs) on the shear behavior of coupling beams to lateral load reversals. The matrix ductility and the reinforcement layout were the main variables of the tests. Three short coupling beams with two different reinforcement arrangements and matrixes were tested. They were subjected to cyclic loading by a suitable experimental setup. All specimens were characterized by a shear span-depth ratio of 1.0. The reinforcement layouts consisted of a classical scheme and diagonal scheme without confining ties. The effects of matrix ductility on deflections, strains, crack widths, crack patterns, failure modes, and ultimate shear load of coupling beams have been examined. The combination of a ductile cementitious matrix and steel reinforcement is found to result in improved energy dissipation capacity, simplification of reinforcement details, and damage-tolerant inelastic deformation behavior. Test results showed that the HPFRCC coupling beams behaved better than normal reinforced concrete control beams. These results were produced by HPHFRCC's tensile deformation capacity, damage tolerance and tensile strength.

• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1540-1555
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• 2021

The plate-type fuel assembly adopted in nuclear research reactor suffers from complicated effect induced by non-uniform irradiation, which might affect its stress conditions, mechanical behavior and thermal-hydraulic performance. A reliable numerical method is of great importance to reveal the complex evolution of mechanical deformation, flow redistribution and temperature field for the plate-type fuel assembly under non-uniform irradiation. This paper is the first part of a two-part study developing the numerical methodology for the thermal-fluid-structure coupling behaviors of plate-type fuel assembly under irradiation. In this paper, the thermal-fluid-structure coupling methodology has been developed for plate-type fuel assembly under non-uniform irradiation condition by exchanging thermal-hydraulic and mechanical deformation parameters between Finite Element Model (FEM) software and Computational Fluid Dynamic (CFD) software with Mesh-based parallel Code Coupling Interface (MpCCI), which has been validated with experimental results. Based on the established methodology, the effects of non-uniform irradiation and fluid were discussed, which demonstrated that the maximum mechanical deformation with irradiation was dozens of times larger than that without irradiation and the hydraulic load on fuel plates due to differential pressure played a dominant role in the mechanical deformation.

• Earthquakes and Structures
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• 제14권3호
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• pp.261-271
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• 2018

Fiber reinforced cementitious composites (FRCC) materials that exhibit strain-hardening and multiple cracking properties under tension were recently developed as innovative building materials for construction. This study aims at exploring the use of FRCC on the seismic performance of coupling beams with conventional reinforcement. Experimental tests were conducted on seven FRCC precast coupling beams with small span-to-depth ratios and one ordinary concrete coupling beam for comparison. The crack and failure modes of the specimens under the low cycle reversed loading were observed, and the hysteretic characteristics, deformation capacity, energy dissipation capacity and stiffness degradation were also investigated. The results show that the FRCC coupling beams have good ductility and energy dissipation capacities compared with the ordinary concrete coupling beam. As the confinement stirrups and span-to-depth ratio increase, the deformation capacity and energy dissipation capacity of coupling beams can be improved significantly. Finally, based on the experimental analysis and shear mechanism, a formula for the shear capacity of the coupling beams with small span-to-depth ratios was also presented, and the calculated results agreed well with the experimental results.

• 한국지진공학회논문집
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• 제10권3호
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• pp.113-123
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• 2006

콘크리트 부재의 내진설계에 있어 강도와 더불어 변형 능력은 중요한 요소이다. 연결보는 전단 지배 부재임에도 항복 이후 소성 변형을 요구하는 부재인데 본 연구에서는 연결보의 변형 능력에 대한 실험을 통해 변형 모형을 제시하였다. 일반적인 배근 형태를 가진 철근 콘크리트 연결보를 대상으로 단조하중실험을 수행하였다. 경간-깊이비, 휨 철근비, 전단 철근비를 변수로 하여 연결보의 거동을 평가하였다. 전단 지배 부재인 연결보는 아치작용과 트러스 작용으로 전단력에 대해 저항하는데 실험 결과를 통해 전단력을 두 작용의 구분과 항복 강도 발현 이후 소성 변형에 따른 두 작용의 구성비 변화에 대해 분석하였다. 실험결과에 기초한 전단 철근과 휨 철근의 변형률 분포 모형을 이용하여 휨 철근의 응력 상태를 산정하였다. 휨 철근의 부착-미끄러짐에 의해 결정되는 균열폭을 고려하는 연결보의 변형 모형을 제시하였다. 항복 상태는 휨 철근의 항복 시점으로 정의하였고, 극한 상태는 변형 증가에 따른 스트럿의 압축 강도 저하에 의해 결정되었다. 이 변형 모형은 변위기초설계에 활용될 수 있을 것으로 기대된다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2005년도 봄학술 발표회 논문집(I)
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• pp.435-438
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• 2005

The use of new hybrid systems that combine the advantages of steel and reinforced concrete structures has gained popularity. One of these new mixed systems consists of steel beams and reinforced concrete shear wall, which represents a cost- and time-effective type of construction. A number of previous studies have focused on examining the seismic response of steel coupling beams in a hybrid wall system. However, the shear transfer of steel coupling beam-wall connections with panel shear failure has not been thoroughly investigated. The objective of this research was to investigate the seismic performance of steel coupling beamwall connections governed by panel shear failure. To evaluate the contribution of each mechanism, depending upon connection details, an experimental study was carried out The test variables included the reinforcement details that confer a ductile behaviour on the steel coupling beam-wall connection, i.e., the face bearing plates and the horizontal ties in the panel region of steel coupling beam-wall connections. It investigates the seismic behaviour of the steel coupling beams-wall connections in terms of the deformation characteristics. The results and discussion presented in this paper provide background for a companion paper that includes a design model for calculating panel shear strength of the steel coupling beam-wall connections.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 추계 학술발표회 제20권2호
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• pp.301-304
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• 2008

본 연구에서는 싱글 플레이트 전단접합에 앵글을 접합한 새로운 방식의 철골 커플링보를 개발하여 여러 가지 구조적 성능을 평가하고자 한다. 주요 변수는 앵글유무, 콘크리트 보강 유무, 매립길이, 결손단면이다. 실험은 커플링 보의 가운데 지점을 2,000kN Actuator를 이용하여 횡방향 반복가력을 가하여 구조물의 전체적인 거동을 알아본다. 실험결과 싱글 플레이트 전단 접합부로 이루어진 실험체보다 앵글을 접합한 실험체가 강도, 변형능력, 강성, 에너지 소산 능력 등 전반적인 구조적 성능이 훨씬 우수한 것으로 나타났다. 매립된 철골보 주위에 전단철근을 보강하지 않은 경우 PC벽체의 조기 지압파괴로 인해 그 성능이 현저히 떨어지는 것으로 나타났다. 그러나 전단철근이 배근이 된 경우 철골 커플링 보의 전단 항복이 발생할 때까지 PC벽체의 파괴가 충분히 지연되는 것으로 나타났다. 앵글이 접합된 경우 매립길이가 작아도 그 성능이 떨어지지 않았다. 결손 단면이 있을 경우 강도는 작게 나타났으나 접합부 전단 강도보다 훨씬 작도록 설계된 관계로 PC벽체의 파괴가 발생하기 전에 충분히 전단 거동을 통해 우수한 성능을 발휘하였다. 이러한 결과는 시공성과 경제성 향상을 위해 앵글을 접합한 철골 커플링 보 방식이 매우 유용할 것으로 사료된다.

• Structural Engineering and Mechanics
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• 제90권4호
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• pp.391-401
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• 2024

The present study focuses on the effect of extension-bending coupling on the elastic stability (buckling) of laminated composite plates. These plates will be loaded under uni-axial or bi-axial in-plane mechanical loads, especially in the orthotropic or anti-symmetric cross-angle cases. The main objective is to find a limit where we can approximate the elastic stability behavior of angularly crossed anti-symmetric plates by the simple behavior of specially orthotropic plates. The contribution of my present study is to predict the explicit effect of extension-flexion coupling on the elastic stability of this type of panel. Critically, a parametric study is carried out, involving the search for the critical buckling load as a function of deformation mode, aspect ratio, plate anisotropy ratio and finally the study of the effect of lamination angle and number of layers on the contribution of extension-flexure coupling in terms of plate buckling stability. We use first-order shear deformation theory (FSDT) with a correction factor of 5/6. Simply supported conditions along the four boundaries are adopted where we can develop closed-form analytical solutions obtained by a Navier development.

• 소성∙가공
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• 제21권7호
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• pp.441-446
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• 2012

A sequential coupled field analysis of electromagnetic free bulging was performed by using FEM. A 2D axi-symmetric electromagnetic model based on the magnetic vector potential is proposed for the calculation of magnetic field and Lorentz's forces. The Newmark integration method is used to calculate the transient dynamic plastic deformation of sheet during free bulging. In the finite element model, the effect of sheet deformation on the electromagnetic field analysis is taken into consideration. In order to confirm the sequential electromagnetic-mechanical coupling analysis, an experiment with an electromagnetic forming apparatus was conducted. The results showed that the final bulge height of the sheet predicted from the proposed method is in good agreement with experimentally measured height.