Spatial representation in product modelling

An unambiguous definition of space is necessary before any attempt is made to develop product or process models for concurrent engineering in the AEC Industry. The ambiguity is the result of different and even conflicting approaches to its definition in the various phases of the building life cycle for different stakeholders, e.g. architects, engineers, and building services engineer etc. Some researchers consider space as an abstract property of things, while others consider it as a thing itself. Regardless of the definition, the space can be referred to as a collector of material objects and also as an object itself. This paper investigates the existing concepts and criteria of definition in various phases, compares the factual and ontological meaning, and specifies conceptual schemas for representation of space, geometry, and buildings

Interoperability-based optimisation of architectural design

As a major contributor to the planetary greenhouse effect, construction industry needs to adopt sustainability at the core of its activities - to reverse or slow down the impacts of climate change. Increased collaboration among stakeholders along with analysis/performance based decision making is the way forward for enhanced sustainability. Emphasis is placed on the process of shared creation through multi-disciplinary collaboration, enabled by the implementation of IT (Information Technology) that acts as a platform to augment our ability to communicate. Developments in the Construction IT have been product oriented and aimed at solving particular domain problems usually with a narrow focus - further reducing the accessibility and interoperability of information over the lifecycle stages. Advances in the semantics based interoperable data standards, such as IFC (Industry Foundation Classes) offer significant advantage in removing such barriers to successful vertical and horizontal integration of software tools and process. The use of building simulation in architectural design requires specialist knowledge and a rich set of information about the proposed building which are not available to the design team at early stages. Standards based mapping of information for input processing of the simulation engines can act as an alternative to simplified tools supporting the exploratory nature of design. Detailed based input processing also restricts the use of simulation to occasional validation of solutions - even during detailed design stages. For a directed exploration of the solution space, numerical optimisation methods can be applied to enhance simulation assisted design. Successful application of optimisation methods pivots on the ability of the analysis and decision making components of the software to communicate with each other without the loss of data semantics. To realise this potential, a process-oriented integrated framework based on the interoperability of information and software tools have been developed and implemented in this thesis. For horizontal integration of domain specific tools through intra-software messaging, ardML - an XML (eXtensible Markup Language) based schema has been developed which attempts to connect non-interoperable software tools. Multi-disciplinary environmental design of buildings has been chosen as the domain of discourse. The framework currently employs industry standard zonal building simulation as an analysis tool and gradient-based mathematical optimisation methods for informed decision making. Interoperability among tools, processes and information has been achieved through the implementation of IFC based data model. The modular nature of the object-oriented framework allows incorporation of existing and future tools. The applicability of the framework has been investigated in the early stages of architectural design, in particular the selection of form and orientation - considering the environmental aspects. The implementation of the framework at an ambiguous and exploratory stage of design reinforces its applicability in a wider industry context