Bim-Oriented Algorithmic Reconstruction of Building Components for Existing Heritage

Abstract

<p><strong>Abstract.</strong> This study is part of a more complex research aimed at establishing guidelines to simplify the digitalization process used to manage existing building heritage. Working in a BIM environment, this paper will present two different algorithms: a modelling algorithm, a data analysis algorithm, and relative applications in the digitalization of a contemporary building. All the archival data required for the digitalization process was collected and those in two-dimensional digital vector format have aroused particular interest because they enabled initiation of the reconstruction process of the BIM model. One of the two algorithms allowed us to identify recurrent elements in a CAD drawing, based on geometric 2D primitives. The final outcome of the first phase involves quadrilateral or circular surfaces and can be viewed in algorithmic environment. The next phase involves applying a unique coloured sign to the identified sections and then export them all in a BIM software. This tool produced unexpected positive results: the presence of a small coloured grid emphasized the discrepancies created between the two-dimensional drawings and the vertical elements. We were thus able to identify the objects with these inconsistencies: they were verified using accurate surveys and then corrected.</p>

Building Archaeology Documentation and Analysis Through Open Source Hbim Solutions via Nurbs Modelling

“…This decision has been taken especially since actual BIM platforms, including open source solutions as FreeCAD, are affected by modelling limitations, based essentially on predefined libraries of theoretical architectural elements as well as the simplified parametric modelling starting from geometric primitives composing main volumes of architectural elements. So, this modelling choice can be adapted for the refectory as well as Cultural Heritage assets purposes, because their features and peculiarities can be hardly represented by using predefined libraries (Adami et al, 2017;Diara et al, 2019;Giannattasio et al, 2019). However, NURBS surfaces and objects aren't parametric models and for this reason they cannot be directly implemented inside a BIM platform, but, as we will see, there are different solutions for the purpose of parametrize NURBS models (Oreni et al, 2014;Diara et al, 2019), allowing to modify construction parameters of 3D objects, according to BIM modelling purposes.…”