• 제목/요약/키워드: design provisions

검색결과 460건 처리시간 0.025초

Solving design optimization problems via hunting search algorithm with Levy flights

  • Dogan, Erkan
    • Structural Engineering and Mechanics
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    • 제52권2호
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    • pp.351-368
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    • 2014
  • This study presents a hunting search based optimum design algorithm for engineering optimization problems. Hunting search algorithm is an optimum design method inspired by group hunting of animals such as wolves, lions, and dolphins. Each of these hunters employs hunting in a different way. However, they are common in that all of them search for a prey in a group. Hunters encircle the prey and the ring of siege is tightened gradually until it is caught. Hunting search algorithm is employed for the automation of optimum design process, during which the design variables are selected for the minimum objective function value controlled by the design restrictions. Three different examples, namely welded beam, cellular beam and moment resisting steel frame are selected as numerical design problems and solved for the optimum solution. Each example differs in the following ways: Unlike welded beam design problem having continuous design variables, steel frame and cellular beam design problems include discrete design variables. Moreover, while the cellular beam is designed under the provisions of BS 5960, LRFD-AISC (Load and Resistant Factor Design-American Institute of Steel Construction) is considered for the formulation of moment resisting steel frame. Levy Flights is adapted to the simple hunting search algorithm for better search. For comparison, same design examples are also solved by using some other well-known search methods in the literature. Results reveal that hunting search shows good performance in finding optimum solutions for each design problem.

Can irregular bridges designed as per the Indian standards achieve seismic regularity?

  • Thomas, Abey E.;Somasundaran, T.P.;Sajith, A.S.
    • Advances in Computational Design
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    • 제2권1호
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    • pp.15-28
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    • 2017
  • One of the major developments in seismic design over the past few decades is the increased emphasis for limit states design now generally termed as Performance Based Engineering. Performance Based Seismic Design (PBSD) uses Displacement Based Design (DBD) methodology wherein structures are designed for a target level of displacement rather than Force Based Design (FBD) methodology where force or strength aspect is being used. Indian codes still follow FBD methodology compared to other modern codes like CalTrans, which follow DBD methodology. Hence in the present study, a detailed review of the two most common design methodologies i.e., FBD and DBD is presented. A critical evaluation of both these methodologies by comparing the seismic performance of bridge models designed using them highlight the importance of adopting DBD techniques in Indian Standards also. The inherent discrepancy associated with FBD in achieving 'seismic regularity' is highlighted by assessing the seismic performance of bridges with varied relative height ratios. The study also encompasses a brief comparison of the seismic design and detailing provisions of IRC 112 (2011), IRC 21 (2000), AASHTO LRFD (2012) and CalTrans (2013) to evaluate the discrepancies on the same in the Indian Standards. Based on the seismic performance evaluation and literature review a need for increasing the minimum longitudinal reinforcement percentage stipulated by IRC 112 (2011) for bridge columns is found necessary.

신뢰성(信賴性) 이론(理論)에 의한 R.C.옹벽(擁壁)의 안정해석(安定解析) 및 설계규준(設計規準) (Reliability Based Stability Analysis and Design Criteria for Reinforced Concrete Retaining Wall)

  • 조태송;조효남;전재명
    • 대한토목학회논문집
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    • 제3권3호
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    • pp.71-86
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    • 1983
  • 현재(現在) WSD로 설계(設計)되고 있는 우리 나라 철근(鐵筋)콘크리트 옹벽구조물(擁壁構造物)에 있어서 가장 보편적으로 사용되고 있는 캔틸레버 옹벽(擁壁)의 안정해석(安定解析) 및 각부설계(各部設計)를 보다 합리적(合理的)이며 확률적(確率的)인 신뢰성(信賴性) 이론(理論)을 도입하여 신뢰성(信賴性) 모델에 따른 안정해석(安定解析) 및 각부설계(各部設計)에 대한 신뢰성(信賴性) 설계규준(設計規準)을 LRFD에 의거하여 제안(提案)하고, 또 안정해석(安定解析)의 공칭안전율(公稱安全率)에 대한 이론적(理論的)인 근거를 제시(提示)하는 것이 본(本) 연구(硏究)의 주요내용(主要內容)이다. 신뢰성(信賴性) 이론(理論)에 의해 안정해석(安定解析) 및 각부설계(各部設計)에 대한 한계상태방정식(限界狀態方程式)을 유도하고, Coulomb의 주동토압계수(主動土壓係數), Hansen의 지지력공식(支持力公式)을 사용하여 Cornell의 MFOSM에 의해 불확실량(不確實量) 산정(算定)의 알고리즘을 유도하였으며 그에 따른 불확실량수준(不確實量水準)은 우리 나라의 현실(現實)을 고려한 적절한 값으로 제안(提案)하였다. 현행(現行) R.C. 옹벽설계규준(擁壁設計規準)에 따라 Calibration 하므로서 목표신뢰성지수(目標信賴性指數)${\beta}_0$를 다음과 같이 선택하고(전도(轉倒): ${\beta}_0$=4.0, 골동(滑動): ${\beta}_0$=3.5, 지지력(支持力): ${\beta}_0$=3.0, 휨: ${\beta}_0$=3.0, 전단(剪斷): ${\beta}_0$=3.2), 이 ${\beta}_0$에 대응하는 하중(荷重) 및 저항계수(抵抗係數)를 산정(算定)하였으며, 안정해석(安定解析)에 대한 현행(現行) 철근(鐵筋)콘크리트 표준시방서(標準示方書)의 안전율(安全率)을 검토한 결과 다음과 같은 값이 적절하다는 것을 알았다(전도(轉倒): 1.8, 골동(滑動): 1.9, 지지력(支持力): 3.6). 또한 현행(現行) WSD R.C. 옹벽(擁壁)의 설계규준(設計規準)을 위해 신뢰성(信賴性)에 의한 공칭안전율(公稱安全率)과 허용응력(許容應力)을 제안(提案)하였다. 그리고 본(本) 연구(硏究)에서 제안(提案)하는 R.C. 옹벽(擁壁)의 LRFD 신뢰성(信賴性) 설계규준(設計規準)을 현행(現行) R.C. 표준시방서(標準示方書)의 설계규준(設計規準)에 대응(對應)하는 설계규준(設計規準)으로 도입함이 바람직하다는 사실을 확인할 수 있었다.

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미국의 실내건축 피난 규정에 관한 연구 - 실내건축계획에 있어 피난 요소를 중심으로 - (A study on the Means of Egress Codes for Interior Architecture in the United States - Focused on Evacuation Elements in the Interior Architectural Design -)

  • 김용성;조성오
    • 한국실내디자인학회논문집
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    • 제27권3호
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    • pp.24-32
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    • 2018
  • The law reflects the situation of the times, understands the society, and shows the will of the state and the community. The Means of Egress should be maintained from design to construction, supervision, as well as use, in order to protect the lives and property of the residents as well as the safe use of the facilities. However, Interior Architects are think that evacuation and safety regulations are complex elements that change frequently and may inhibit the idea of design. The purpose of this study is to propose a design method for the use of safe facilities in the interior architectural design on the evacuation regulations affecting the actual design by the IBC(the International Building Code) and NFPA(National Fire Protection Association) LSC (Life Safety Code). The research method is to investigate and analyze the provisions related to the evacuation of interior architecture in the US and to understand the current regulations and the evacuation regulations. We suggest to design method to the details of the hallway, corridors, aisle accessway, door way, exit path, In particular, the design of furniture, tables and chairs layout that could be obstacles to evacuation situations is presented.

The EC3 approach to the design of columns, beams and beam-columns

  • Nethercot, D.A.;Gardner, L.
    • Steel and Composite Structures
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    • 제5권2_3호
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    • pp.127-140
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    • 2005
  • Procedures given in Eurocode 3 Part 1.1 (EN 1993-1-1) for design of the main types of structural member under given systems of loading are presented and described. Whereas some of these e.g. the procedure for axially loaded columns, are little changed from the early concept that appeared more than 25 years ago in the European Recommendations and have subsequently been adopted in many other steel codes of the world, others such as the interaction formulae for beam-columns are new, with aspects of the provisions still under development. For each type of member the basis of the procedure is described and some comparative comments made.

Licensing Approach for New Fuel Design

  • Ahn, Seung-Hoon;Park, Jun-Sang;Auh, Geun-Sun;Koo, Bon-Hyun;Lee, Seung-Hyuk
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1998년도 춘계학술발표회논문집(2)
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    • pp.1026-1031
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    • 1998
  • A licensing approach for new fuel design is propose. It includes the possible licensing options to be taken according to the level of significance of design changes. This approach can be applied on legal grounds of the AEA, Article 44.3 and Article 21, but implies that the related ERAEAs should be revised or other alternative regulatory guidelines should be prepared. However, it is not intended to invoke additional requirements but rather to streamline and formulate the current practice by using one of supplementary provisions of the AEA, Article 104.2 which is recently enacted for approval of the technical report on a special topic.

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콘크리트와 철근의 부착강도에 대한 횡구속 설계변수 (Design Parameters of Confinement on Bond Strength of Reinforcing Steel to Concrete)

  • 김상준;이재열;이웅세;최완철
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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    • pp.653-658
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    • 1999
  • Bond between reinforcing bars and the surrounding concrete is supposed to safely transfer load in the design process of reinforced concrete structures. Bond failure of reinforcing bars generally take place by splitting of concrete cover as bond force between concrete and reinforcing bars exceeds the resistance by the confinement of the concrete cover and transverse reinforcement. Confinement, concrete cover and transverse reinforcement, on bond are the key factor of current provision to determine development length of reinforcing bars to concrete. In this study, previous available data are analyzed with respect to the current provisions for development and splice of reinforcement. From this study, the new provision for the design are proposed, which will be efficient and effective with some specific limit value.

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집합주거 단지내의 커뮤니티 형성에 관한 이론적 고찰 (Design Elements for Community facility in Housing Complex)

  • 김학균;김정곤
    • 한국주거학회논문집
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    • 제12권2호
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    • pp.123-132
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    • 2001
  • The purpose of this study is to analyze the elements of community Design for urban housing complex, and to suggest design criteria for urban housing. It is recognized that the community facilities has to fit within the urban fabric. However with a correct focus, the community activities can acquire its own identity around which its internal social and economic activities can flourish. A community needs a focus and a well ordered hierarchy of all amenities in a balanced and cohesive environment. This has been achieved within the framework of following parameters as follows: Focus and Identity of community, Cohesion of areas and activities, Accessibility of general facilities, Community and institutional provisions, Safety and Hierarchy of commercial activities.

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비틀림 거동을 하는 구조물의 설계 편심 (The Design Eccentricity for Torsionally Unbalanced Structure)

  • 조소훈;이명규
    • 한국지진공학회논문집
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    • 제5권5호
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    • pp.63-72
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    • 2001
  • 본 논문에서는 구조물의 안전성과 경제성을 함께 도모하도록 하기 위하여 모드 해석법을 이용하여 비틀림 거동을 하는 구조물의 동적 거동을 정적 하중으로 치환할 경우에 대한 횡하중 중심점을 가정하고, 횡하중 중심점과 구조물의 강도 중심을 일치시키도록 구조물의 설계 편심을 조절하는 방법을 제안한다. 그리고 제안된 방법에 의해 구조물을 설계하였을 경우, 다른 내진 기준에 의해 설계된 구조물과 비교하여 지나친 추가 연성도를 요구하지 않는다는 것을 보여준다.

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철골-콘크리트 합성 연결보의 거동과 설계 (Behavior and Design of Steel-Concrete Composite Coupling Beams)

  • 홍성걸;양지연
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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    • pp.433-438
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    • 2003
  • Structural steel/composite beams provide a viable alternative for coupling individual reinforced concrete wall piers. Well-established guidelines for shear links in eccentrically braced steel frames form the basis of current design guidelines. However, these provisions ignore the effects of nominally reinforced concrete encasement which typically surrounds the coupling beam, and are based on overly conservative assumed deformation demand. A coordinated analytical research program at here has focused on response of steel/composite coupling beams, their connections to reinforced concrete walls, and overall behavior of composite coupled wall systems. Using the results from this study, guidelines for proper design and detailing of steel/composite coupling beams and beam-wall connections have been developed. This paper summarizes the research program, and highlights the basic concepts, important findings, and recommendations.

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