접합부의 비선형 거동을 고려한 강뼈대 구조물의 고등해석과 최적설계

최세휴,박문호,송재호,임청권,Choi, Se Hyu,Park, Moon Ho,Song, Jae Ho,Lim, Cheong Kweon 한국강구조학회 2003 韓國鋼構造學會 論文集 Vol.15 No.6

The advanced analysis and optimal design of semi-rigid frame were presented. Advanced analysis can predict the combined nonlinear effects of connection, geometry, and material on the behavior and strength of semi-rigid frames. The Kishi-Chen power model was used to describe the nonlinear behavior of semi-rigid connections. Geometric nonlinearity was determined using stability functions. On the other hand, material nonlinearity was determined using the Column Research Council (CRC) tangent modulus and parabolic function. The direct search method proposed by Choi and Kim was used as optimization technique. The member with the largest unit value evaluated using the LRFD interaction equation was replaced one by one with an adjacent larger member selected from the database. The objective function was assumed as the weight of steel frame, with the constraint functions accounting for load-carrying capacities, deflections. inter-story drifts, and ductility requirement. Member sizes determined by the proposed method were compared with those derived using the conventional LRFD method. 본 논문에서는 접합부의 비선형을 고려한 강뼈대 구조물의 고등해석과 최적설계를 수행하였다. 고등해석은 접합부의 비선형, 기하학적 비선형 및 재료적 비선형을 고려한다. 접합부의 비선형은 Kishi와 Chen이 제안한 3가지 매개변수를 가지는 파워모델을 사용하여 고려하였다. 기하학적 비선형은 안정함수를 사용하여 고려하였으며, 재료적 비선형은 CRC 접선 탄성계수와 포물선 함수를 사용함으로서 고려하였다. 최적화 기법으로는 Choi와 Kim이 제안한 직접탐색법을 사용하였다. 직접탐색법은 LRFD의 상관방정식으로 계산된 값중에서 최대값을 가지는 부재의 크기를 단계별로 증가시키는 방법이다. 목적함수는 구조물의 중량을 사용하였으며, 제약조건식은 구조시스템의 하중-저항능력, 처짐, 층간 수평변위 및 연성요구 조건을 고려하였다. 제안된 방법에 의한 설계결과를 LRFD방법과 비교하였다.

접합부의 비선형 거동을 고려한 공간 강뼈대 구조물의 고등해석과 최적설계

최세휴,Choi, Se Hyu 한국강구조학회 2004 韓國鋼構造學會 論文集 Vol.16 No.5

본 논문에서는 접합부의 비선형을 고려한 공간 강뼈대 구조물의 고등해석과 최적설계를 수행하였다. 고등해석은 접합부의 비선형, 기하학적 비선형 및 재료적 비선형을 고려한다. 접합부의 비선형은 Kishi와 Chen이 제안한 3가지 매개변수를 가지는 파워모델을 사용하여 고려하였다. 기하학적 비선형은 안정함수를 사용하여 고려하였으며, 재료적 비선형은 CRC 접선 탄성계수와 포물선 함수를 사용함으로서 고려하였다. 최적화 기법으로는 Choi와 Kim이 제안한 직접탐색법을 사용하였다. 직접탐색법은 LRFD의 상관방정식으로 계산된 값중에서 최대값을 가지는 부재의 크기를 단계별로 증가시키는 방법이다. 목적함수는 구조물의 중량을 사용하였으며, 제약조건식은 구조시스템의 하중-저항능력, 처짐, 층간 수평변위 및 연성요구 조건을 고려하였다. 제안된 방법에 의한 설계결과를 LRFD방법과 비교하였다. Advanced analysis and optimal design of semi-rigid space steel frames were presented. The advanced analysis can predict the combined nonlinear effects of connection, geometry, and material on the behavior and strength of semi-rigid frames. The Kishi-Chen power model was used to describe the nonlinear behavior of semi-rigid connections. Geometric nonlinearity was determined using stability functions. Material nonlinearity was determined using the Column Research Council (CRC) tangent modulus and the parabolic function. The direct search method proposed by Choi and Kim was used as optimization technique. One by one, the member with the largest unit value evaluated using the LRFD interaction equation were placed adjacent to a larger member selected from the database. The objective function was assumed to be the weight of steel frame, while the constraint functions were load-carrying capacities, deflections, inter-story drifts, and the ductility requirements. The member sizes determined using the proposed method were compared to those derived from the conventional LRFD method.

강아치교의 고등해석과 최적설계

최세휴,Choi, Se Hyu 한국강구조학회 2005 韓國鋼構造學會 論文集 Vol.17 No.1

본 논문에서는 강아치교의 고등해석과 최적설계를 수행하였다. 고등해석은 해석시에 구조계와 그에 속한 부재의 강도와 안정을 직접 고려함으로서, 해석후 개별부재의 강도검토가 필요없는 설계방법을 지칭한다. 기하학적 비선형 효과를 고려하기 위하여 안정함수를 사용하였다. 잔류응력으로 인한 점진적인 소성화를 고려하기 위하여 CRC 접선 탄성계수를 사용하였다. 탄성강성에서 완전소성강성까지 점진적인 소성화를 나타내기 위하여 포물선 함수를 사용하였다. 최적화 기법으로는 수정된 단면점증법을 사용하였다. 수정된 단면점증법은 AASHTO-LRFD의 상관방정식으로 계산된 값중에서 최대값을 가지는 부재의 크기를 단계별로 증가시키는 방법이다. 목적함수는 구조물의 중량을 사용하였으며, 제약조건식은 구조시스템의 하중-저항능력 및 처짐 조건을 고려하였다. 제안된 방법에 의한 설계결과를 기존의 연구결과와 비교하였다. Advanced analysis and optimal design of steel arch bridges is presented. In the design method using an advanced analysis, separate member capacity checks after analysis are not required because the stability and strength of the structural system and its component members can be rigorously treated in the analysis. The geometric nonlinearity is considered by using the stability function. The Column Research Council tangent modulus is used to account for gradual yielding due to residual stresses. A parabolic function is used to represent the transition from elastic to zero stiffness associated with a developing hinge. An optimization technique used is a modified section increment method. The member with the largest unit value evaluated by AASHTO-LRFD interaction equation is replaced one by one with an adjacent larger member selected in the database. The objective function is taken as the weight of the steel arch bridge and the constraint functions account for load-carrying capacities and deflection requirements. Member sizes determined by the proposed method are compared with those given by other approaches.

고등해석과 유전자 알고리즘을 이용한 반강접 강뼈대 구조물의 직접설계시스템의 최적화

최세휴(Se Hyu Choi) 한국강구조학회 2006 韓國鋼構造學會 論文集 Vol.18 No.6

고등해석을 이용한 강구조물의 직접설계시스템 개발

최세휴(Choi Se-Hyu),박문호(Park Moon-Ho),장준호(Chang Chun-Ho) 한국구조물진단유지관리학회 2003 한국구조물진단학회 학술발표회논문집 Vol.- No.-

A new design method of three-dimensional frames using practical advanced analysis is presented. In this method separate member capacity checks encompassed by the code specifications are not required, because the stability of separate members and the structure as a whole can be rigorously treated in determining the maximum strength of the structures. To capture second-order effects associated with P-6 and P-Δeffects, stability functions are used to minimize modeling and solution time. The Column Research Council (CRC) tangent modulus concept is used to account for gradual yielding due to residual stresses. A softening plastic hinge. Kishi-Chen power model is used to describe the nonlinear behavior of semi-figid connections. The load-displacements predicted by the proposed analysis compare well with those given by other approaches. A design examples has been presented for a 22-story frame. The analysis results show that the proposed method is suitable for adoption in practice.

고등해석을 이용한 반강접 공간 강뼈대 구조물의 최적설계

최세휴(Choi Se Hyu),박문호(Park Moon Ho),김상진(Kim Sang Jin),박정활(Park Jung Hwal) 대한토목학회 2004 대한토목학회 학술대회 Vol.2004 No.10

토목공학을 위한 표준 이수체계도에 관한 연구

최세휴(Se-Hyu Choi),박성식(Sung-Sik Park) 한국공학교육학회 2012 공학교육연구 Vol.15 No.1

This study present the standard flow chart for civil engineering considering Korean education environment. The flow charts of USA s 20 universities and Korea s 6 universities are investigated. The standard flow chart are proposed based on the standard curriculum of civil engineering and flow charts of USA and Korea though analyzing of prerequisite of each subject. The proposed standard flow chart is expected when used to improve korean universities curriculum.

토목공학을 위한 표준 교과과정에 관한 연구

최세휴(Se-Hyu Choi),노태송(Tae-Song Noh) 한국공학교육학회 2011 공학교육연구 Vol.14 No.4

This study present the standard curriculum for civil engineering considering korean education environment. The flow charts of USA s 20 universities and Korea s 6 universities are investigated. The standard curriculum are proposed based on the civil engineering curriculum of USA and Korea though analyzing of subject division, major field, and major subject. The proposed standard curriculum is expected when used to improve korean universities curriculum.

K-EP(K-Engineering Professional) 자격을 위한 졸업생역량 평가방안 연구

최세휴(Choi, Se Hyu),강상희(Kang, Sang Hee),김정수(Kim, Jung Soo),윤지영(Yoon, Jiyoung) 한국공학교육학회 2021 공학교육연구 Vol.24 No.6

The present study aims to demonstrate that it is possible to objectively evaluate the competency (referred to as graduate attributes or program outcomes) of graduates of engineering education programs. To strengthen the link between engineering education accreditation and the qualification/certification system of engineering professionals, referred to as K-Engineering Professional (K-EP), individually assuring the quality of accredited graduates using multiple-choice test as main assessment tool is proposed. Test questions related to the basic vocational skills of NCS are developed for seven of the 10 program outcomes of the ABEEK KEC2015. The three program outcomes, PO1, PO3, and PO5, which need to fully accommodate the characteristics of each disciplinary field, are excluded. A pilot test involving graduates of eight accredited programs is conducted. Applying on Rasch model based on Item Response Theory (IRT), the item difficulty, fit and discrimination of multiple choice test are demonstrated. The pilot study strongly suggests that individual competency evaluation is possible at a certain level for seven program outcomes tested. For PO1, PO3, and PO5, however, questions that address the characteristics of each disciplinary field need to be devised. If a suitable pool of questions is built, it can be used as a program outcomes assessment tool by the accredited programs.

풍속지형계수 산정방법

최세휴(Choi, Se Hyu),서은수(Seo, Eun su) 대한토목학회 2013 대한토목학회 학술대회 Vol.2013 No.10