• Journal of the Korean Wood Science and Technology
• /
• 제45권5호
• /
• pp.535-543
• /
• 2017

목구조물 기둥-보 접합물로는 슬릿 가공된 부재에 강판을 삽입한 형상이 통용되고 있다. 본 연구에서는 접합부가 접착된 강절형 문형라멘프레임 및 강판 대용인 목질접합물을 제작하여 절반은 기둥부재에 일체화하고 나머지 절반은 보부재와 핀으로 접합한 반강절형 문형라멘프레임을 제작하였다. 목질 문형라멘프레임들은 강판삽입형 접합부 문형라멘프레임과 수평내력성능을 비교 분석하였다. 수평내력성능은 완전탄소성모델 분석과 구간별 강성변화율 및 단기허용전단내력으로 평가하였다. 실험결과, 강절형 문형라멘프레임의 최대내력이 강판삽입형 접합부 문형라멘프레임 보다 낮게 측정되어 항복 내력은 0.58, 종국내력은 0.48로 산출되었으나, 초기강성과 소성률은 각각 1.35, 1.1 향상된 값이 측정되었다. 반강절형 문형라멘프레임의 완전탄소성모델 분석 결과 최대내력은 강절형 문형라멘프레임보다 낮았으나 파괴 후 인성이 우수하여 종국내력은 1.05~1.07 높은 값이 산출되었다. 강판삽입형 문형라멘프레임은 반복 시험이 진행됨에 따라 강성이 급격히 감소한 반면 접합부가 목질로된 문형라멘프레임들의 강성은 서서히 감소되었다.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2003년도 사면안정학술발표회
• /
• pp.93-101
• /
• 2003

Steel frame-type retaining walls(SFRW) are constructed by on site bolting of prefabricated steel frames and internal filling of materials such as rocks with the size of 150-300mm. Easy & fast construction, superior drainage performance and structural performance to rigorous site conditions are some of the merits of applying the SFRW to various construction sites. After the development of the structural details, a test construction of SFRW, with the height of 6m and 30m in length, was carried out at an apartment site. After completion, several months of monitoring was carried out on the structure to check displacement, tilting, settlement, soil pressures and drainage characteristics. The results of the structural behavior of SFRW along with its construction methods are presented in the paper.

• Steel and Composite Structures
• /
• 제4권5호
• /
• pp.403-418
• /
• 2004

Lateral sway is most likely to control the design of semi-rigid steel frames where the frame arrangements do not include any form of bracing. This paper investigates the sway behaviour of semi-rigid regular steel frames i.e., frames having the same arrangement of beam and column sections at all levels, and hence proposes some design charts for the prediction of sway that eliminate the need for doing any numerical modelling. Schueller's equation has also been modified to incorporate connection flexibility in addition to its original rigid frame considerations. All the proposed methods have been validated using results obtained from numerical analysis.

• Structural Engineering and Mechanics
• /
• 제55권3호
• /
• pp.535-554
• /
• 2015

Dolphin echolocation (DE) optimization algorithm is a recently developed meta-heuristic in which echolocation behavior of Dolphins is utilized for seeking a design space. The computational performance of meta-heuristic algorithms is highly dependent to its internal parameters. But the computational time of adjusting these parameters is usually extensive. The DE is an efficient optimization algorithm as it includes few internal parameters compared with other meta-heuristics. In the present paper a modified Dolphin echolocation (MDE) algorithm is proposed for optimization of steel frame structures. In the MDE the step locations are determined using one-dimensional chaotic maps and this improves the convergence behavior of the algorithm. The effectiveness of the proposed MDE algorithm is illustrated in three benchmark steel frame optimization test examples. Results demonstrate the efficiency of the proposed MDE algorithm in finding better solutions compared to standard DE and other existing algorithms.

• Advances in Computational Design
• /
• 제2권1호
• /
• pp.29-42
• /
• 2017

This study presents algorithms for determining the fuzzy critical loads of planar steel frame structures with fixity factors of beam - column and column - base connections are modeled as triangular fuzzy numbers. The finite element method with linear elastic semi-rigid connection and Response Surface Method (RSM) in mathematical statistic are applied for problems with symmetric triangular fuzzy numbers. The ${\alpha}$ - level optimization using the Differential Evolution (DE) involving integrated finite element modeling is proposed to apply for problems with any triangular fuzzy numbers. The advantage of the proposed methodologies is demonstrated through some example problems relating to for the twenty - story, four - bay planar steel frames.

• Earthquakes and Structures
• /
• 제10권5호
• /
• pp.1111-1123
• /
• 2016

To study seismic performance of steel frame-bent structure, one specimen with one-tenth scale, three-bay, and five-story was tested under reversed cyclic lateral load. The entire loading process and failure mode were observed, and the seismic performance indexes including hysteretic loops, skeleton curve, ductility, load bearing capacity, drift ratio, energy dissipation capacity and stiffness degradation were analyzed. The results show that the steel frame-bent structure has good seismic performance. And the ductility and the energy dissipation capacity were good, the hysteresis loops were in spindle shape, which shape were full and had larger area. The ultimate elastic-plastic drift ratio is larger than the limit value specified by seismic code, showing the high capacity of collapse resistance. It can be helpful to design this kind of structure in high-risk seismic zone.

• Steel and Composite Structures
• /
• 제24권3호
• /
• pp.369-382
• /
• 2017

This study investigates the reliability of the performance levels of moment resisting steel frames subjected to lateral loads such as wind and earthquake. The reliability assessment has been performed with respect to three performance levels: serviceability, damageability, and ultimate limit states. A four-story moment resisting frame is used as a typical example. In the reliability assessment the uncertainties in the loadings and in the capacity of the frame have been considered. The wind and earthquake loads are assumed to have lognormal distribution, and the frame resistance is assumed to have a normal distribution. In order to obtain an appropriate limit state function a linear relation between the loading and the deflection is formed. For the reliability analysis an algorithm has been developed for determination of limit state functions and iterations of the first order reliability method (FORM) procedure. By the method presented herein the multivariable analysis of a complicated reliability problem is reduced to an S-R problem. The procedure for iterations has been tested by a known problem for the purpose of avoiding convergence problems. The reliability indices for many cases have been obtained and also the effects of the coefficient of variation of load and resistance have been investigated.

• Steel and Composite Structures
• /
• 제24권3호
• /
• pp.383-391
• /
• 2017

The goal of this study is to investigate structural analysis and behaviors of an innovative aerial work platform truss frame whose ductility is improved by using high strength-steel UL-700. The present space truss frame can move or stop through tunnels for maintenance constructions by automatic facilities and workmanship within standardized limited building lines of tunnel. Most of all, this method overcomes problematic, which is to block cars during construction periods, seriously, of typical methods like as using truck and scaffolds for tunnel maintenance. According to evaluated appropriate design results of space truss frames of numerical examples by using a commercial MIDAS GEN program, it is verified that design parameters such as layered size, cross-sectional size, and steel material of the present space truss frame are determined to depend on characteristics such as lanes or shape of road tunnels.

• 한국공간구조학회:학술대회논문집
• /
• 한국공간구조학회 2008년도 춘계 학술발표회 논문집
• /
• pp.212-217
• /
• 2008

본 논문은 앙골라 주경기장에 대한 구조설계에 대해 설명하고 있다. 앙골라 주경기장은 연면적 78,000$m^2$, 지상 4층 구조물로서 스탠드 부분은 Steel moment frame으로 구성되고, 지붕부분은 캔틸래버 트러스 시스템으로 설계되었다. 기초는 파일기초가 사용되었으며, 내진과 내풍설계, 스탠드 부분에 대한 다이아프램 액션, 스탠드와 지붕사이의 Interaction, 바닥진동 등 사용성 평가가 설계사항에 고려된 프로젝트이다.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2000년도 춘계학술대회논문집A
• /
• pp.67-72
• /
• 2000

Demand for now nondestructive evaluation are growing to detect fatigue crack growth behavior to predict long term performance of materials and structure in aggressive environments especially when they are In non-visible area. Acoustic emission technique is well suited to these problems and has drawn a keen interests because of its dynamic detection ability, extreme sensitivity and location of growing defects. In this study, we analysed acoustic emission signals obtained in fatigue and tensile test of high strength fire resistance steel for frame structure with time-frequency analysis methods. The main frequency range is different in the noise and the fatigue crack propagation. It could be classified that it were also generated by composite fracture mechanics of cleavage, dimple, inclusion separation etc.