Mahjoub M. Elnimeiri Biography Dr. Mahjoub M. Elnimeiri holds a B. Sc. In Civil Engineering (with Honors) from the University of Khartoum; a D.I.C. and M. Sc. in Structural Engineering from the Imperial College, University of London, London, England and a Ph.D. in Structural Engineering and Structural Mechanics from Northwestern University, Evanston, Illinois, USA. Since his educational completion in 1974, he has been involved in the practice of
structural and architectural work of buildings in Chicago, USA and overseas. His expertise is in the areas of structural analysis, design and construction of buildings, and in particular tall buildings, and in the application of computer technology. He is very active and well known in the professional and academic communities. He has been speaker in many conferences and conventions. His publications are directly related to his areas of study, and he is a recipient of the “State of The Art Award” of the American Society of Civil Engineers for the year 1989. Dr Elnimeiri is Chairman of CECI+ Engineers International, Chicago, Illinois, USA. CECI+ is a progressive engineering firm using cutting edge of technology for service provision to its clients. The practice includes structural analysis, design and overseeing construction of very special buildings, primarily tall buildings, at different places in US and overseas. Few of these buildings are located in highly seismic areas. Before beginning his own practice, Dr Elnimeiri worked with Skidmore Owings & Merrill, Chicago from 1979-1990. During his experience at SOM, he worked closely with Architectural Partners in the design development of many outstanding projects. Dr Elnimeiri left SOM as an Associate Partner and Senior Structural Engineer. Dr Elnimeiri is also a full professor, Founder & Director of the PhD Program, at the College of Architecture at Illinois Institute of Technology, Chicago, Illinois, USA.
Presenter Photo
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CTBUH 2011 World Conference October 10-12, 2011, COEX, Seoul, KOREA_____________________________________________________________________________________________________________________________________________________________
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CTBUH 2011 World Conference October 10-12, 2011, COEX, Seoul, KOREA_____________________________________________________________________________________________________________________________________________________________
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CTBUH 2011 World Conference October 10-12, 2011, COEX, Seoul, KOREA_____________________________________________________________________________________________________________________________________________________________
1975, there was a meaningful collaboration between the architect and the structural engineer. A good example for that is John Hancock Building in Chicago, 1996, (Figure 4). However energy efficiency strategies were never considered in this building.
As mentioned above, the development of tall buildings had been traditionally a product of a close collaboration between the architect and the engineer. Since in the design process, the most important design decisions, those which have the most significant cost impacts, are made at the concept stage of a project, the collaboration between different disciplines within the design team in this stage become very important. Barriers to this collaboration often have resulted in that small and large architectural firms either left the sophisticated modeling of environmental metrics until too late in the design process, or they neglect it altogether (Galasiu and Reinhart, 2007), so as a result they would come up with inefficient architectural form. To address such disconnect, this research paper propose a digitally-based workflow to aid direct interaction among energy efficiency, structural performance and formal design considerations to assist early design activities. Parametric Design Within the last years digital tools have extensively progressed so as to allow the architects to increasingly become involved in an integrative collaborative architectural building design approaches. In these years, digital media is not used as a representational tool for visualization but as a generative tool for the derivation of form and its transformation.
Figure 5. Tall Building Generation Process by Parametric Design (Courtesy of Park, 2005)
Figure 4. John Hancock Center, Chicago, USA. (Courtesy of Skidmore
Owings and Merrill)
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CTBUH 2011 World Conference October 10-12, 2011, COEX, Seoul, KOREA_____________________________________________________________________________________________________________________________________________________________
In the last few decades computer simulations have proven to be a powerful digital tool for studying the environmental performance of buildings. By using simulation and analysis tools, it is possible to engage in an architectural design practice that is significantly enhanced by iterative process that depends on feedback from the evaluation of the environmental impact into the architectural design decision making. (shown in Figure 6). Among various digital design approaches, parametric design has become a strong trend in contemporary architectural design practice and education (Day, 2010). The term refers to a practice of digitally modeling a series of design variants whose relationships to each other are defined through one or several mathematical relationship (parameters), then form a parametric space that may comprise of tens or hundreds of related but distinct forms. By relying on parametric values, it becomes possible to associate variables, relations, and dependencies to geometry and structure in the design process (Dominik, Jiwu, Mike & Mark, 2004). This facilitates rapid editing, re-adaptability, and enables useful libraries of scripts and reusable parts for future use. Hence these parametric modeling systems help the architect to rapidly generate and test a large number of design options and variation in the early stage of design by linking the generative tools to structural, energy efficiency analysis and evaluation tools. This approach minimizes performance-based study time and aids the project team in making better informed decisions earlier in the design process. Extending the potential of parametric/associative models to respond to both structural and energy efficiency inputs and performance criteria is the main focus of this research.
Proposed Workflow In this work, we emphasize mainly on a general trend to architectural form design approaches defining mostly the basics of performance strategies of tall buildings. The advantage of parametric design in research application is to plan and synthesize the overall requirements and relationships of many design elements into one form. The convergence of generative tools, analytical solutions and moving away from traditional form-driven approaches are the main achievements. Various parametric modeling platforms have been employed to simply evaluate how changes in architectural forms of a tall building would affect its structural performance as well as its energy efficiency.
Figure 6. Parametric modeling processes and solar
incidence angle analysis for the Lotte Tower project
in Seol, Korea (Courtesy of Skidmore, Owings &
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CTBUH 2011 World Conference October 10-12, 2011, COEX, Seoul, KOREA_____________________________________________________________________________________________________________________________________________________________
This research paper demonstrates how a fixable 3D model can be parametrically altered towards targeted solutions with the help of a near real time feedback generated by structural/energy analysis and optimization. The main focus in this work is defining the architectural model in a way to be parametrically reconfigurable while at the same time remains dynamically responsive to performance-based engineering input. The architectural model will be kept in a fluid state allowing for intuitive variations according to the feedback from performance-based data. All different solutions can be analyzed and evaluated according to ones objective and preference. Energy performance analysis, in parallel with structural analysis, is performed on the parametric models through an optimization framework leading to a considerably faster performance-based study. It is shown that, the proposed workflow gives the architect the opportunity to select among different design options based on ones objectives. Using this workflow to simulate environmental and structural performance provides a visualization of results with color mapping, enabling performance to be easily understood by all members of the design team.
Figure 8. Proposed Workflow
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CTBUH 2011 World Conference October 10-12, 2011, COEX, Seoul, KOREA_____________________________________________________________________________________________________________________________________________________________
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CTBUH 2011 World Conference October 10-12, 2011, COEX, Seoul, KOREA_____________________________________________________________________________________________________________________________________________________________
ConclusioThis researnamely formthat are to bflexible enoperformancdeveloped efficiency coa well-roundIn such casobjectives; it is better solutions. Tthat manipu Reference [1] http://ww[2] Bazjana
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CTBUH 2011 World Conference October 10-12, 2011, COEX, Seoul, KOREA_____________________________________________________________________________________________________________________________________________________________
[5] Caldas L. G. and Norford L. K. (2001) A Design Optimization Tool Based on a Genetic Algorithm, Automation Construction, pp. 173 – 184.
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Hierarchical Geometry Relation”, Automation in Construction 18, 2009, pp. 825–833.
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