Stathis Eleftheriadis | University College London (original) (raw)

Papers by Stathis Eleftheriadis

Research paper thumbnail of Investigating relationships between cost and CO 2 emissions in reinforced concrete structures using a BIM-based design optimisation approach

An integrated design approach for the cost and embodied carbon optimisation of reinforced concret... more An integrated design approach for the cost and embodied carbon optimisation of reinforced concrete structures is presented in this paper to inform early design decisions. A BIM-based optimisation approach that utilises Finite Element Modelling (FEM) and a multi-objective genetic algorithm with constructabil-ity constraints is established for that purpose. A multilevel engineering analysis model is developed to perform structural layout optimisation, slab and columns sizing optimisation, and slab and columns reinforcement optimisation. The overall approach is validated using real buildings and the relationships between cost and carbon optimum solutions are explored. The study exhibits how cost effective and carbon efficient solutions could be obtained without compromising the feasibility of the optimised designs. Results demonstrate that the structural layout and the slab thickness are amongst the most important design optimisation parameters. Finally, the overall analysis suggests that the building form can influence the relationships between cost and carbon for the different structural components.

Research paper thumbnail of Multilevel Computational Model for Cost and Carbon Optimisation of Reinforced Concrete Floor Systems

The cost and carbon efficiency of building structures could be enhanced by the current developmen... more The cost and carbon efficiency of building structures could be enhanced by the current developments in design automation and optimisation techniques. New ways to systematically assess design alternatives based on cost and carbon parameters are necessary. The study proposes a multilevel optimisation approach that combines Building Information Modelling (BIM) data and Finite Element Modelling (FEM) with a constrained genetic algorithm. The optimisation methodology is tested in a prototypical building floor system. Structural grid configurations, floor thicknesses and columns sizes and reinforcement details are identified. The results showed that the cost optimum design is 3% cheaper than the carbon optimum design but it has 7% more carbon. In addition, the concrete in the floor is the biggest contributor in both total cost and carbon. Relationships between cost-and carbon-optimum designs for the tested structural configuration are also discussed.

Research paper thumbnail of Augmented BIM based taxonomy for steel design systems: An integrated evolutionary computational approach

Research paper thumbnail of BIM Enabled Optimisation Framework For Environmentally Responsible And Structurally Efficient Design Systems

The present research investigates the potential for reducing the environmental impacts of structu... more The present research investigates the potential for reducing the environmental impacts of structural systems through a more efficient use of materials. The main objective of this research is to explore and to develop a holistic and integrated methodology that utilises Building Information Modelling's (BIM) capabilities combined with structural analysis and Life Cycle Assessment (LCA) as well as a two-staged structural optimisation solver that achieves efficient and environmentally responsible steel design solutions. The implemented workflow utilises Autodesk Revit -BIM, Tally -LCA and Autodesk Robot -Structural Analysis. RobOpt is the plug-in that has been established using the Application Programming Interface (API) of Robot and the .NET framework of C♯, and it inherits several structural functionalities based on Robot Finite Element Method (FEM) engine. The proposed RobOpt application can be accessed via a graphic user interface (GUI) within the Robot software. The developed BIM-enabled optimisation methodology could be utilised as a design tool to inform early stage structural design solutions. A prototypical steel framed structural system under certain loads has been explored. The resulting bespoke I-beam sections from the custom genetic algorithm (GA) optimisation demonstrate that significant savingsup to 21% -can be achieved in all tested environmental indicators when compared to the standard UK catalogue of steel sections. Considering all, the proposed framework constitutes a useful and an intuitive workflow, which aims to quantify the environmental savings of structural systems by utilising, advanced computational analysis and common construction techniques.

Research paper thumbnail of Life cycle energy efficiency in building structures: A review of current developments and future outlooks based on BIM capabilities

The continuous developments of Building Information Modelling (BIM) in Architecture, Engineering ... more The continuous developments of Building Information Modelling (BIM) in Architecture, Engineering and Construction (AEC) industry supported by the advancements in material resourcing and construction processes could offer engineers the essential decision-making procedures to leverage the raising demands for sustainable structural designs. This article brings together the theory of Life Cycle Assessment (LCA) and the capabilities of BIM to survey the current developments in the energy efficiency of structural systems. In addition, the article explores the engineering dimensions of common decision-making procedures within BIM systems including optimisation methods, buildability and safety constraints and code compliance limitations. The research presents critical expositions in both engineering and sustainable energy domains. The article then argues that future innovations in the sustainable decision-making of buildings' structures would require BIM-integrated workflows in order to facilitate the conflicting nature of both energy efficient and engineering performance indexes. Finally, the study puts forward a series of research guidelines for a consolidated decision paradigm that utilises the capabilities of BIM within the engineering and sustainable energy domains in a synergistic manner.

Research paper thumbnail of Investigating relationships between cost and CO 2 emissions in reinforced concrete structures using a BIM-based design optimisation approach

An integrated design approach for the cost and embodied carbon optimisation of reinforced concret... more An integrated design approach for the cost and embodied carbon optimisation of reinforced concrete structures is presented in this paper to inform early design decisions. A BIM-based optimisation approach that utilises Finite Element Modelling (FEM) and a multi-objective genetic algorithm with constructabil-ity constraints is established for that purpose. A multilevel engineering analysis model is developed to perform structural layout optimisation, slab and columns sizing optimisation, and slab and columns reinforcement optimisation. The overall approach is validated using real buildings and the relationships between cost and carbon optimum solutions are explored. The study exhibits how cost effective and carbon efficient solutions could be obtained without compromising the feasibility of the optimised designs. Results demonstrate that the structural layout and the slab thickness are amongst the most important design optimisation parameters. Finally, the overall analysis suggests that the building form can influence the relationships between cost and carbon for the different structural components.

Research paper thumbnail of Multilevel Computational Model for Cost and Carbon Optimisation of Reinforced Concrete Floor Systems

The cost and carbon efficiency of building structures could be enhanced by the current developmen... more The cost and carbon efficiency of building structures could be enhanced by the current developments in design automation and optimisation techniques. New ways to systematically assess design alternatives based on cost and carbon parameters are necessary. The study proposes a multilevel optimisation approach that combines Building Information Modelling (BIM) data and Finite Element Modelling (FEM) with a constrained genetic algorithm. The optimisation methodology is tested in a prototypical building floor system. Structural grid configurations, floor thicknesses and columns sizes and reinforcement details are identified. The results showed that the cost optimum design is 3% cheaper than the carbon optimum design but it has 7% more carbon. In addition, the concrete in the floor is the biggest contributor in both total cost and carbon. Relationships between cost-and carbon-optimum designs for the tested structural configuration are also discussed.

Research paper thumbnail of Augmented BIM based taxonomy for steel design systems: An integrated evolutionary computational approach

Research paper thumbnail of BIM Enabled Optimisation Framework For Environmentally Responsible And Structurally Efficient Design Systems

The present research investigates the potential for reducing the environmental impacts of structu... more The present research investigates the potential for reducing the environmental impacts of structural systems through a more efficient use of materials. The main objective of this research is to explore and to develop a holistic and integrated methodology that utilises Building Information Modelling's (BIM) capabilities combined with structural analysis and Life Cycle Assessment (LCA) as well as a two-staged structural optimisation solver that achieves efficient and environmentally responsible steel design solutions. The implemented workflow utilises Autodesk Revit -BIM, Tally -LCA and Autodesk Robot -Structural Analysis. RobOpt is the plug-in that has been established using the Application Programming Interface (API) of Robot and the .NET framework of C♯, and it inherits several structural functionalities based on Robot Finite Element Method (FEM) engine. The proposed RobOpt application can be accessed via a graphic user interface (GUI) within the Robot software. The developed BIM-enabled optimisation methodology could be utilised as a design tool to inform early stage structural design solutions. A prototypical steel framed structural system under certain loads has been explored. The resulting bespoke I-beam sections from the custom genetic algorithm (GA) optimisation demonstrate that significant savingsup to 21% -can be achieved in all tested environmental indicators when compared to the standard UK catalogue of steel sections. Considering all, the proposed framework constitutes a useful and an intuitive workflow, which aims to quantify the environmental savings of structural systems by utilising, advanced computational analysis and common construction techniques.

Research paper thumbnail of Life cycle energy efficiency in building structures: A review of current developments and future outlooks based on BIM capabilities

The continuous developments of Building Information Modelling (BIM) in Architecture, Engineering ... more The continuous developments of Building Information Modelling (BIM) in Architecture, Engineering and Construction (AEC) industry supported by the advancements in material resourcing and construction processes could offer engineers the essential decision-making procedures to leverage the raising demands for sustainable structural designs. This article brings together the theory of Life Cycle Assessment (LCA) and the capabilities of BIM to survey the current developments in the energy efficiency of structural systems. In addition, the article explores the engineering dimensions of common decision-making procedures within BIM systems including optimisation methods, buildability and safety constraints and code compliance limitations. The research presents critical expositions in both engineering and sustainable energy domains. The article then argues that future innovations in the sustainable decision-making of buildings' structures would require BIM-integrated workflows in order to facilitate the conflicting nature of both energy efficient and engineering performance indexes. Finally, the study puts forward a series of research guidelines for a consolidated decision paradigm that utilises the capabilities of BIM within the engineering and sustainable energy domains in a synergistic manner.