EVOLUTION OF THE PROJECT

2. EVOLUTION OF THE PROJECT

The reconstruction of a building is in iterative and often a recursive process based on an data set that typically grows and changes significantly while project time progresses. A parametric BIM is much more flexible than classic 2d3d drawings. The use of a parametric architectural model allows for a change in design even at a later time in the working process, because of the possibility to access the original geometric definition at all times. This is especially helpful for extensive building research projects that frequently produce new evidence in the course of the ongoing work e.g. through new findings on excavation sites. It is important to note that the possibility of changes in the model later in the workflow should not result in imprecise work at any stage of the project. 2.1 BIM support a non-linear workflow Furthermore the approach allows for a step by step working process from the reconstruction of coarser to finer elements. Thus projects can be realized within a given time frame. In effect the modeling of historic buildings can benefit from the so called BIM method Building Information Modeling, as the necessary structuring of the basic data renders it into very sustainable information. This also means that the applied rules and parameters of the geometry generation remain clear, comprehensible and editable for all other users of the data. 2.2 Teamwork and documentation of data A BIM allows for the separate investigation of sub-projects. Parts of the modeling that appear too complex at a given point of time, may be filled with placeholders and individual working groups of a team can tackle different work packages simultaneously. As a result a basic model of the bulding emerges rapidly from data and the level of detail may be increased with time. It is important to note that team work requires thorough coordination and that standards and templates should be defined prior or as early as possible in the project. 2.3 Ready and open for future developments and technology Building Information Modeling is also open for technological advances and can readily take advantage of new computing power, i.e. cloud computing. Documentation and storage formats of a BIM become important in the long run. It is important to note that digital data should be stored in a sustainable digital format to allow future users to work with the data. 2.4 Parametric modeling approach A parametric modeling approach is best suited for similar shapes that can be derived of each other parametrically, e.g. Capitals or Gothic tracery Figs. 5, 6, 7. Furthermore the method can be used for the generation of simplified abstract models, for example for plausibility checks during the reconstruction process. The method’s advantages can be described particularly with its simple way of adding new data to the model and the adaptive level of displayed detail. The use of pre-defined component libraries facilitates collaborative teamwork, allowing numerous scientists to work simultaneously on one reconstruction project. The resulting models, so-called Solid models, are not only quite suitable for weight calculations but can be equally well applied as the basis of 3d model prints. Fig. 5 Parametric variation of the height of a window Fig. 6 Parametric variation of the base of a column Fig. 7 Variation of the level of detail 163

3. THE PROCESS OF RECONSTRUCTION