Application of Scan-to-BIM approaches to HBIM digitisations in Architectural Heritage environment for documentation, management and conservation purposes

The operative methodology of this research has been tailored upon the purposes illustrated in the last paragraph, to validate an improved framework for optimising HBIM models which enable an interpretation of the AH buildings as correct and complete as possible. Indeed, albeit Scan-to-BIM could be considered nowadays a well-established framework, this research tried some experimental procedures aimed at empowering both the quantitative and qualitative aspects of the digitisation, especially affecting data acquisition and the manual modelling phases.The data acquisition through MDCSs techniques and their post-processing are canonical routines which provide the most reliable outputs for the reality-based models; however, in the next chapters different capturing methodologies have been tested either through their integration or their comparison in order to evaluate their effectiveness in detecting a sufficiently accurate initial information tailored to the scopes of both the surveys and the models. The direct, manual approach with manual methods still represents the most used and valid method in modelling; despite this, to overcome its notorious limitations, it has been sided by some novelties, offering alternative workflows, tools and libraries whenever the standard ones provided by the BIM environment were not satisfactory for the CH management needs.These testbeds were focused on:✓the digitisation of atypical architectural items through the NURBS modelling;✓the integration of heterogeneous, queryable data inside the models, enabling further investigations and thematic mapping;Once the trustworthiness of this new dynamic framework has been benchmarked from a computational point of view, it could be serialised and implemented on a standard basis for providing more precise solutions to the most recurring issues in the generative parametrisation and the documentation of the historical evidence of the Architectural Heritage.In order to validate the main purposes of development phase of this research, the improved framework illustrated in the last paragraph has been applied on four case studies. The first three cases, all belonging to the medieval AH in Sicily, have the same architectural, constructive and stylistic features. In order of presentation, they are the churches of San Giovanni dei Lebbrosi and San Giovanni degli Eremiti in Palermo, followed by the so-called Trinità di Delia in Castelvetrano (Trapani, Western Sicily).Their digitisation led to:✓the establishment of an adequate framework for a data acquisition campaign, capable of collecting and delivering more efficient information and their related outputs;✓the adoption of improved modelling procedures from point clouds for typical construction families (columns, walls, floors and roofs);the implementation of a small library of parametric and customisable elements related to a peculiar historic/architectural style;The fourth case study is a cave Baroque church dug into an archaeological Punic settlement in Marsala (Western Sicily), named Santa Maria della Grotta. It offered the possibility:✓to document in an integral way a densely stratified area which hadn’t been surveyed before;✓to test an experimental procedure for the thematic mapping of decay alterations affecting the real artifact;✓to create an expandable database collecting all the semantic information relevant to the decay monitoring and tailored on CH management purposes;These buildings have been chosen because their digitisation could be relevant not only from a historical/architectural point of view but for all the technical and methodological aspects as well, as an actual testbed to benchmark the experimentations illustrated ahead against.Their models thus obtained establish and offer a generalized and repeatable framework for other modellers in similar cases.