# I-BIM Applied in Railway Geometric Inspection Activity: Diagnostic and Alert
## 1 Introduction  
Building Information Modeling (BIM) methodology is currently applied in the construction domain, with a growing spread across different domains of the sector, revealing an evident recognition of the benefits achieved with its implementation [1]. The basic concept consists of the digital representation of a three-dimensional (3D) BIM virtual model, using the selection, adjustment and definition of parametric objects, to produce an accurate digital representation in a 3D shape and with physical properties [2]. This primary notion has been overtaken by the strategy of manipulating the model database for different types of tasks, such as construction planning (4D BIM model) or facility management (7D BIM model) [3, 4, 5]. In distinct sectors, and by observing the enormous potential of the BIM model database, there has been a strong trend to develop add-ins, plug-ins and extensions, associated to BIM software, and, more recently, the elaboration of specific scripts making use of Dynamo 3.3 (2025) or Python 3.13.3 (2025) programming languages [6, 7, 8]. The most recent developed scripts essentially consider the manipulation and generation of new data with the aim of adding value to BIM models, generated for each building or infrastructure project. In the present work, a Dynamo script was developed, allowing an increase in the BIM model ability with the insertion of the inspection's railway data, the evaluation of the information related to geometric anomalies detected over the railway track components and the association of a color code correlated to the severity of the identified geometric inaccuracies [9]. Regarding the implementation of BIM in the railway project and maintenance, the available technical literature presents only a few scientific reports and publications; however, this topic, along with the different domains of the construction industry, has recently perceived a strong improvement in the real potential application of BIM. There is currently widespread interest in applying BIM methodology in a large spectrum of areas, from the design of bridges [10] to the preservation of heritage buildings [11]. This evident technological advance is driven by government directives that bet on BIM to establish a growing degree of digital transformation in construction [12]. While the term BIM is fundamentally applied to the building sector, the term Infrastructure Building Information Modeling (I-BIM) denotes the projects related to transport infrastructures [13]. The generation of I-BIM models, concerning railway infrastructure, requires the definition of new specific parametric objects representing the railway track components, as the availability of software libraries with objects of infrastructure components is limited, and the creation of new objects assigned to specific parameters is a time-consuming effort. The present research is oriented to analyze the I-BIM methodology implementation focused on railway inspection activity. Currently, the significant use of the train, as a preferred means of transport, has led to an increased level of infrastructure degradation and a necessity for more maintenance actions, followed by the necessary restitution of the required capacity of the railway network. The level of the service quality of the railway infrastructure has begun to deteriorate, as a consequence of the material degradation of its components, caused fundamentally by the circulation of the trains, but also by the track's exposure to the natural environment [14]. Railway enterprises must keep the train rails in good condition for the safety of the passengers, as badly damaged rails can cause not just service delays but catastrophic accidents. The anomalies found in the railway infrastructure frequently cause serious vibrations, and have the potential to cause accidents, putting the lives of the train passengers in danger.