No abstract

In the construction field, the Building Information Modeling (BIM) methodology is becoming increasingly predominant and the standardization of its use is now an essential operation. This method has become widespread in recent years, thanks to the advantages provided in the framework of project management and interoperability. Hoping for its complete dissemination, it is unthinkable to use it only for new construction interventions. Many are experiencing what happens with the so-called Heritage Building Information Modeling (HBIM); that is, how BIM interfaces with Architectural Heritage or simply with historical buildings. This article aims to deal with the principles and working methodologies behind BIM/HBIM and modeling. The aim is to outline the themes on which to base a new approach to the instrument. In this way, it can be adapted to the needs and characteristics of each type of building. Going into the detail of standards, the text also contains a first study regarding the classification of moldable elements. This proposal is based on current regulations and it can provide flexible, expandable, and unambiguous language. Therefore, the content of the article focuses on a revision of the thinking underlying the process, also providing a more practical track on communication and interoperability.

<p><strong>Abstract.</strong> In urban areas, the “built” is defined by many different elements. Not only buildings but also open spaces containing green areas, viability, urban furniture, underground facilities. While the H-BIM sector focuses, rightly, on buildings of great historical significance, in our case it is been consider a part of the built that it usually not analyse: the urban open space. One of the interesting themes is the possibility of having a single tool that integrates the different objects present in a complex environment such as the urban area. The process with BIM model could allow a huge saving in terms of time and costs considering public tender, maintenance or construction phase of a project. Facility management operating through BIM is another relevant theme considering the whole life of a construction. Finally, another important theme is the connections between elements above the ground (visible elements) and subsoil (not visible elements), not only for the administrations but also if related to the HBIM environment.</p><p>The paper reports the analysis of the experience performed, particularly related to questions about detail and accuracy of the BIM model.</p><p>A methodology for modelling open spaces is been assuming, it is described possible improvements and considerations on the result.</p>

The aim of this work is to present a method for the tolerance analysis of an assembly involving free-form surfaces based on dimensional and geometric tolerances. The great effort of the present work is to deal with dimensional and geometric tolerances applied to free-form surfaces. The case of study is the flaperon, a structural component of the aircraft, that is constituted by one skin cover, eight ribs, and one spar. The ten components of the flaperon are connected by adhesive, in order to overcome the problems due to the rivets use. Adhesive thickness between the faced parts to connect should be as constant as possible in order to obtain the right structural connection. The influence of the tolerances applied to the ten components of the flaperon on the value of the gap at the interfaces among each couple of components has been deeply investigated by means of the proposed method. Moreover, the influence of the tolerances on the aerodynamic performances of the flaperon has also been analyzed.

The new methodologies of surveying and modelling allow for important advantages in the whole life cycle of a building. Specifically, the point cloud, with its richness in detail, can be the basis to set an interesting and useful work of creating a BIM model. Inside, all the objects with a well-structured informative part allow for the interoperability between the different figures involved in the process. One of the main aims can be the use of a BIM model to manage the competitive tender in the public works in order to control time and costs. The case study is about urban open space: analysis of digital and integrated management of a built environment.