삼각형 메쉬 곡면의 측지선과 적용

손수덕,Shon, Su-Deok 한국공간구조학회 2012 한국공간구조학회지 Vol.12 No.4

양자비트와 양자기반 탐색 알고리즘의 연산자

손수덕,이돈우,하준홍,이승재,Shon, Sudeok,Lee, Donwoo,Ha, Junhong,Lee, Seungjae 한국공간구조학회 2021 한국공간구조학회지 Vol.21 No.4

막 구조물의 재단도 작성과 막재의 손실률에 관한 연구

손수덕,정을석,김승덕,Shon, Su-Deok,Jeong, Eul-Seok,Kim, Seung-Deog 한국공간구조학회 2006 한국공간구조학회지 Vol.6 No.1

경량 연성구조시스템 중 하나인 막 구조물은 대공간 구조물에 많이 사용되어진다. 막 구조물은 축강성이 강하고 휨강성이 매우 작은 재료를 주 구조재로 사용하기 때문에 다른 구조물과 달리 구조설계에서는 형상해석, 응력-변형해석 그리고 재단도 등의 일련의 과정을 필요로 한다. 재단도의 작성에는 구조물의 크기나 곡률 그리고 재료적 강성에 따라 많은 변수가 작용하며 다른 설계과정과는 매우 다르다. 따라서 일반 구조설계용 프로그램은 막 구조물의 구조설계에 부적당하다. 본 연구에서는 막 구조물의 측지선을 이용한 재단도 작성 프로그램을 개발하고, 예제를 통해 재단도 작성결과를 비교 고찰하도록 한다. Membrane structures, a kind of lightweight soft structural system, are used for spatial structures. The design procedure of membrane structures are needed to do shape finding, stress-deformation analysis and cutting pattern generation, because the material property has strong axial stiffness, but little bending stiffness. The problem of cooing pattern is highly varied in their size, curvature and material stiffness. So, the approximation inherent in cutting pattern generation methods is quite different. Therefore the ordinary computer software of structural analysis & design is not suitable for membrane structures. In this study, we develop the program for cooing pattern generation using geodesic line, and investigate the result of example's cooing pattern in detail.

막 구조물의 초기형상해석과 재단도 작성에 관한 연구

손수덕,정을석,김승덕,안상길 대한건축학회 2006 大韓建築學會論文集 : 構造系 Vol.22 No.5

Membrane structures, a kind of lightweight soft structural system, are many used for large spatial stadium or gymnasium. The material property of the membrane has strong tensional stiffness, but little bending. The design procedure of membrane structures are needed to do shape finding, stress-deformation analysis and cutting pattern generation. In shape finding, membrane structures are unstable structures initially. These soft structures need to be introduced initial stresses because of its initial unstable state, and happen large deformation phenomenon. Also there are highly varied in their size, curvature and material stiffness. So, the approximation inherent in cutting pattern generation methods is quite different.Therefore, in this study, to find the structural shape after large deformation caused by initial stress, we have done the shape analysis considering geometric nonlinear term. And the geodesic line on surface of initial equilibrium shape and the cutting pattern generation using the geodesic line is introduced.

Shape control of cable structures considering concurrent/sequence control

손수덕,Alan S. Kwan,이승재 국제구조공학회 2014 Structural Engineering and Mechanics, An Int'l Jou Vol.52 No.5

In this study, the control of the shape of pre-stressed cable structures and the effective control element were examined. The process of deriving the displacement control equations using the force method was explained, and the concurrent control scheme (CCS) and the sequence control scheme (SCS) were proposed. To explain the control scheme process, the quadrilateral cable net model was adopted and classified into a regular model and an irregular model for the analysis of the control results. In the control analysis of the regular model, the CCS and SCS analysis results proved reliable. For the SCS, the errors occur in the control stage and varied according to the control sequence. In the control analysis of the irregular model, the CCS analysis result also proved relatively reliable, and the SCS analysis result with the correction of errors in each stage was found nearly consistent with the target shape after the control. Finally, to investigate an effective control element, the Geiger cable dome was adopted. A set of non-redundant elements was evaluated in the reduced row echelon form of a coefficient matrix of control equations. Important elements for shape control were also evaluated using overlapping elements in the element sets, which were selected based on cable adjustments.

형상에 따른 주름강판의 탄성전단좌굴 특성 및 경향성 분석 연구

손수덕,이승재,유미나 한국구조물진단유지관리공학회 2014 한국구조물진단유지관리공학회 논문집 Vol.18 No.6

This paper aims at comparing and analyzing shear buckling characteristics between sinusoidal corrugation shape and trapezoidalone. For this, I adopted the equal-length trapezoidal corrugation and sinusoidal one for the analytical models, and analyzed theirshear buckling characteristics through linear buckling analysis and on its theory. Generally, the shear buckling shapes of corrugatedsteel plates are classified into local buckling, global buckling, and interactive buckling from the two buckling modes. Sinusoidalcorrugation shape, unlike trapezoidal corrugation, does not have flat sides, which causes another tendency in shear buckling mode. Especially, the changes and different aspects of shear buckling on the boundary between local buckling and global buckling appearin different corrugation shapes. According to the analysis results, interactive buckling mode appeared on the boundary of localbuckling and global bucking in trapezoidal corrugation. However, in the case of corrugated steel plates with sinusoidalconfiguration, interactive buckling mode appeared in the part where global bucking takes place. Besides, trapezoidal shapes are ofadvantages on shear buckling resistance in the local buckling section, and so are sinusoidal shapes in the global buckling section. 본 연구는 정현형 주름과 마름모형 주름 형상의 전단좌굴 특성을 비교, 분석하는 것이 목적이다. 이를 위해서 동일한 길이의 마름모꼴주름과 정현파주름을 해석대상모델로 채택하였으며, 선형좌굴해석을 통한 전단좌굴특성과 이론식에 의한 특성을 분석하였다. 일반적으로주름강판의 전단좌굴 형태는 국부좌굴, 전체좌굴 및 두 좌굴에 의한 연성좌굴로 분류된다. 그러나 마름모꼴주름과는 달리 정현파주름형상은 평평한 면이 없기 때문에 전단좌굴의 양상에 대한 경향이 달라진다. 특히 국부좌굴과 전체좌굴의 경계에서 나타나는 전단응력변화와 양상은 주름형태에 의해 차이가 난다. 분석 결과에서 볼 때, 제형 (마름모꼴)의 경우는 이론식내의 전체좌굴과 국부좌굴의 경계에서 연성좌굴모드가 발생했다. 그러나 정현파형의 경우 전체좌굴이 발생하는 구간에서 연성좌굴모드가 발생하는 양상을 보였다. 또한 국부좌굴 구간에는 제형형상이 그리고 전체좌굴 구간에서는 정현파형상이 전단좌굴에 저항하는데 유리하게 작용하였다.

돔형 스페이스 프레임 구조물의 하중모드에 따른 분기점 특성에 관한 연구

손수덕,김승덕,이승재,김종식 한국공간구조학회 2011 한국공간구조학회지 Vol.11 No.1

스페이스 프레임 구조물은 연속체 쉘 구조물의 원리를 이용하여 매우 넓은 공간을 효과적 으로 덮을 수 있는 구조물이지만 뜀좌굴 및 분기좌굴 등과 같은 불안정거동은 돔형 구조물에서는 더욱 복잡하게 나타난다. 또한 붕괴메커니즘의 이론적 연구와 실험적 연구결과들 사이에서도 많은 차이를 보인다. 본 논문에서는 미적 효과가 크며 단층의 대공간을 확보하기에 적합한 돔형 공간 구조물의 구조 불안정 특성을 접선강성방정식을 이용하여 비선형 증분해석을 수행하고, Rise-span(μ)비 및 하중모드(RL)에 따른 임계점과 분기점의 특성을 돔형 공간구조물의 예제를 통해 고찰하였다. 여기서 불안정점은 증분해석과정을 통해서 예측할 수 있었으며, 예제에서 낮은 μ에서는 전체좌굴이, 높은 μ의 경우는 절점좌굴이 지배적이며, 낮은 RL에서 정점좌굴이, 높은 RL에서는 전체좌굴이 지배적이고, 전체좌굴이 나타나는 경우, 분기좌굴하중은 완전형상의 극한점좌굴하중의 약 50%에서 70%의 분포를 보였다. Space frame structures have the advantage of constructing a large space structures without column and it may be considered as a shell structure. Nevertheless, with the characteristics of thin and long term of spacing, the unstable problem of space structure could not be set up clearly, and there is a huge difference between theory and experiment. Therefore, in this work, the tangential stiffness matrix of space frame structures is studied to solve the instability problem, and the nonlinear incremental analysis of the structures considering rise-span ratio(μ) and the ratio of load(RL) is performed for searching unstable points. Basing on the results of the example, global buckling can be happened by low rise-span ratio(μ), nodal buckling can be occurred by high rise-span ratio(μ). And in case of multi node space structure applying the ratio of load(RL), the nodal buckling phenomenon occur at low the ratio of load(RL), the global buckling occur a1 high the ratio of load(RL). In case of the global buckling, the load of bifurcation is about from 50% to 70% of perfect one's snap-through load.

Minimum Weight Design of Sinusoidal Corrugated Web Beam using Differential Evolution Algorithm

손수덕,유미나,강주원,이승재 한국강구조학회 2015 International Journal of Steel Structures Vol.15 No.1

Due to their many advantages, corrugated steel plates are widely used in various applications including bridges. Starting withairplane design, these corrugated steel plates have been used in civil engineering applications such as buildings and bridges,and many studies on corrugated steel plates are being conducted. However, most of these studies focused on the strength ofgirders through analysis and experiment of corrugated steel plates and studies on the optimization of corrugated steel plates arestill insufficient. The present study developed the weight optimum design using the differential evolution and investigated theeffects of parameters. The optimization program was verified with differential evolution through the numerical analysisexamples of simple beams and fixed beams. For this verification, the optimization program using the genetic algorithm thathas been studied was compared with the weight optimum graph of the optimization program of differential evolution proposedin this study. As a result, the graphs of these two optimization programs increased similarly. The change rate was 3.57% orlower in the example of uniformly load for fixed beam, 1.60% or lower in the example of concentrated load for fixed beam,and 1.44% or lower in the example of uniformly load for simple beam. Furthermore, in the graph of changing design variables,the changing web thickness showed a similar trend as the increasing trend of the optimum sectional area.

유로코드를 이용한 주름웨브보의 최적설계 연구

손수덕,유미나,이승재,Shon, Su-Deok,Yoo, Mi-Na,Lee, Seung-Jae 한국공간구조학회 2012 한국공간구조학회지 Vol.12 No.4

This paper describes the structural design and optimization of sinusoidally corrugated web girder by using EUROCODE (EN 1993-1-5). The optimum design methodology and characteristics of the optimal cross-section are discussed. We investigate a shear buckling and the concerned standards for corrugated web and explain the equations to obtain a critical stress according to buckling type. In order to perform optimization, we consider an objective function as minimum weight of the girder and use the constraint functions as slenderness ratio and stresses of flanges as well as corrugated web and deflection. Genetic Algorithm is adopted to search a global optimum solution for this mathematical model. For numerical example, the clamped girder under the concentrated load is considered, while the optimum cross-sectional area and design variables are analyzed. From the results of the adopted example, the optimum design program of the sinusoidally corrugated web girder is able to find the suitable solution which satisfied a condition subject to constraint functions. The optimum design shows the tendency to decrease the cross-sectional area with the yielding strength increase and increase the areas with load increase. Moreover, the corrugated web thickness shows a stable increase concerning the load.

돔형 스페이스 프레임 구조물의 하중모드에 따른 분기점 특성에 관한 연구

손수덕,김승덕,이승재,김종식 한국공간구조학회 2011 한국공간구조학회지 Vol.11 No.1

Space frame structures have the advantage of constructing a large space structures without column and it may be considered as a shell structure. Nevertheless, with the characteristics of thin and long term of spacing, the unstable problem of space structure could not be set up clearly, and there is a huge difference between theory and experiment. Therefore, in this work, the tangential stiffness matrix of space frame structures is studied to solve the instability problem, and the nonlinear incremental analysis of the structures considering rise-span ratio(μ) and the ratio of load(R_L) is performed for searching unstable points. Basing on the results of the example, global buckling can be happened by low rise-span ratio(μ), nodal buckling can be occurred by high rise-span ratio(μ). And in case of multi node space structure applying the ratio of load(R_L), the nodal buckling phenomenon occur at low the ratio of load(R_L), the global buckling occur at high the ratio of load(R_L). In case of the global buckling, the load of bifurcation is about from 50% to 70% of perfect one's snap-through load. 스페이스 프레임 구조물은 연속체 쉘 구조물의 원리를 이용하여 매우 넓은 공간을 효과적으로 덮을 수 있는 구조물이지만 뜀좌굴 및 분기좌굴 등과 같은 불안정거동은 돔형 구조물에서는 더욱 복잡하게 나타난다. 또한 붕괴메커니즘의 이론적 연구와 실험적 연구 결과들 사이에서도 많은 차이를 보인다. 본 논문에서는 미적 효과가 크며 단층의 대공간을 확보하기에 적합한 돔형 공간 구조물의 구조 불안정 특성을 접선강성방정식을 이용하여 비선형 증분해석을 수행하고, Rise-span(μ)비 및 하중모드(R_L)에 따른 임계점과 분기점의 특성을 돔형 공간구조물의 예제를 통해 고찰하였다. 여기서 불안정점은 증분해석과정을 통해서 예측할 수 있었으며, 예제에서 낮은 μ에서는 전체좌굴이, 높은 μ의 경우는 절점좌굴이 지배적이며, 낮은 R_L에서 절점좌굴이, 높은 R_L에서는 전체좌굴이 지배적이고, 전체좌굴이 나타나는 경우, 분기좌굴하중은 완전형상의 극한점좌굴하중의 약 50%에서 70%의 분포를 보였다.