Digital wood trusses. geometry and parameters/fabrication and monitoring

This paper aims to demonstrate how to translate features and properties of existing wooden structures about function, performance and aesthetic into BIM objects. This purpose has a double effect: from an operative perspective, the modelling of existing wooden structures is necessary for any structural restoration project, while culturally for the preservation of construction techniques and their transferability in the current design theory. This refers in particular to wooden trusses as compound objects, such as to comply with a single structural and configurative purpose within the built space. The study proves the feasibility of describing the relationship among geometry, material features, construction techniques and simulation of trusses within a BIM environment. From a methodological point of view, starting from a point cloud, the process involves the modelling of beams and trusses, the construction of a library of nodes with parametric geometry drawn from nineteenth-century treatises (also called “wood stereotomy”), the information exchange from the BIM object to structural simulation environment. Moreover, there is the development of a parametric relation structure, which enables the creation of cutting parameters of the truss’s structural components. The case study from which the system is obtained is the covering system of the Church of the Eremitani, which hosts a so-called revolutionary covering system by a fourteenth-century monk, Giovanni degli Eremitani.