Analysis of international experience in the field of building information modelling of transport infrastructure objects

In this paper, the authors consider the current state and level of implementation of building information modeling applied to transport infrastructure at the stages of their life cycle in Russia and abroad. Possible prerequisites for the transfer of knowledge and technologies of building information modeling from the civil and industrial facilities to the field of transport construction are highlighted according to the accumulated experience in the design, construction and operation of such facilities in various countries and Russia. Special emphasis is placed on examples of the world's largest implemented or ongoing projects for the construction of transport infrastructure. The experience of implementing these projects was analyzed from the point of view of the software used in relation to all stages of the life cycle of transport infrastructure objects: design, construction and subsequent operation. The prospects for the development of data exchange formats in the context of the existing problem of mutual integration of BIM and GIS for transport infrastructure objects to ensure their complementarity and compatibility are also considered. The functional levels of the use of various software within the framework of companies implementing project activities using information modeling technologies are highlighted. A list of criteria characterizing the level of information modeling technologies integration to transport infrastructure objects into the activities of participants in the life cycle of these objects is highlighted. A review of the regulatory framework of information modeling in construction in Russia is carried out, and the main differences in this area with the regulatory regulation of this area in the European Union are noted. Conclusions are made about the key reference points for the development of information modeling of transport infrastructure facilities on a national scale, leading customer companies and contractors.


Introduction
Building information modeling (BIM) technologies are actively implemented in the construction of civil and industrial facilities around the world [1,2,3,4] and in Russia [5,6,7,8]. Their impact on the cost, construction time, the possibility of eliminating errors in the design and the transparency of the construction process itself have been evaluated by many research groups [3,9,10,11], as well as directly during work on many large infrastructure facilities [4,5,12,13].
At the same time, the introduction of information modeling for transport infrastructure facilities at the present stage is largely different from the experience of using these technologies in civil and industrial construction [14,15]. This is due both to the need to create a unified model for its geographically distributed parts, located at a considerable distance from each other, and to the widespread development in the transport industry of the use of geographic information systems (GIS) tools [16,17].
In this regard, the purpose of the paper is to review the existing experience, technologies and knowledge in this area in order to form the conceptual foundations for the implementation of information modeling technologies in the construction of transport infrastructure (railway infrastructure -in particular) on the territory of the Russian Federation. To achieve this goal, it is necessary to: x Conduct an analysis of the world experience in the implementation of information modeling technologies in the construction of transport infrastructure facilities; x highlight the detailed structure of design systems based on the main process events accompanying the development of the project at the stage of construction and operation; x conduct a review of the current state of the construction and transport industries in terms of information modeling technologies in Russia; x review the current state of ensuring data interoperability at the junction of the use of BIM and GIS technologies.

Methods and materials
World experience of information modeling technologies implementation in the construction of transport infrastructure

The review of major infrastructure projects
According to the analysis of publications from international databases, large infrastructure projects related to railway construction were identified. There are some projects with different levels of use of information modeling technologies in the world in recent years: x RailBaltica project, European Union. This project is part of the Trans-European Transport Network (TEN-T Holding), Germany. The German Federal Transport Agency has set a digital design and construction goal for all large-scale government projects from 2020. That is why Deutsche Bahn AG, the main operator of German railways, has already implemented 13 pilot projects using BIM technology and plans to scale up the experience gained in the future [25]. At the same time, in matters of organizing the digital modeling and construction process, there is a similarity with the already mentioned Crossrail project, where strict requirements were put forward for all contractors in terms of design standards in relation to common data environments and company systems. x Implementation of construction projects by Maharashtra Metro Rail Corporation Limited (Maha Metro), India. The company is currently building two major rail projects in the cities of Nagpur and Pune, with a total length of 38,215 km and 31,254 km, respectively. As in the case of previous projects, strict design standards were set for all contractors by the company. The company created a common data environment based on Bentley ProjectWise Design Integration and Bentley Asset Wise CDE. Thus, two characteristic features can be noted that accompany the implementation of large infrastructure projects in the field of railway construction: the mandatory development of customer requirements for information implementation of the project (EIR), as well as the organization of a common data environment based on software systems.

BIM maturity levels
Basically, researchers distinguish several levels of BIM maturity, which are separated by the volumes used, formats and forms of exchange and use of data in the project [26,27,28,29]: x BIM 1.0. Convert 2D to 3D. It is typical for this level that most of the project participants do not work in the BIM environment, and 2D drawings remain the main means of communication.
x BIM 2.0. Parallel BIM. The second level is characterized using BIM for important parts of the project: in areas where the interaction of participants is required, areas with complex geometry. x BIM 3.0. Integrated BIM. For the third level, it is characteristic that all the main project participants will create BIM-models and work with them. x BIM 4.0. Intelligent BIM (AI BIM). This phase is characterized by the accumulation and analysis of big data by integrating BIM with sensors and multiple databases, which will improve the efficiency of informed decision-making. The main criteria for the division are the forms of exchange and use of data in the project, while in order to translate the successful experience of introducing BIM technologies from the construction of industrial and civil facilities to the construction of transport infrastructure, it is necessary to analyze a more detailed functional structure of design systems based on the identification of the main process events accompanying the development of the project at the stage of construction and operation. The authors of the study suggest a similar structure below: both organizational issues and issues of the professional level of project participants at each stage of implementation. The high dependence of the level of BIM technologies maturity in a project on the professional level of its performers is noted by many researchers [30,31]. The experience of many countries [32,33,34,35] shows that the implementation of new training programs based on secondary specialized and higher educational institutions, as well as retraining and advanced training programs can effectively solve personnel issues related to the need of new competencies for all project participants. So, in Singapore, the level of 100% use of BIM in design organizations was achieved in 2015, the entire process of transformation of the industry was accompanied by the participation of a specialized training and research unit -BCA Academy. This division provides educational services at all levels: from training construction workers to training managers. And all this is in close connection with information modeling technologies, around which a new set of competencies and skills of all participants in construction projects is being formed.

Main software and its' functional levels
Within the framework of the infrastructure projects discussed above, as well as in other projects of companies presented in scientific studies [18-26, 36, 37], the used software complexes were complexes that are part of the ecosystem of products of Autodesk and Bentley Systems.
At the same time, many participants in the Russian and foreign markets note [38,39] that the high quality of project execution is ensured by the presence of a wide range of software at various functional levels, the structure of which the authors of this study suggest below in Figure 1:

Review of the current state of the construction and transport industries in terms of information modeling technologies in Russia The regulation of information modeling implementation in Russia
According to the decree of the Government of the Russian Federation dated March 5, 2021 No. 331, from January 1, 2022, for capital construction projects (CCP) financed with the involvement of funds from the budgetary system of the Russian Federation, the formation and maintenance of the CCP information model must be ensured. Moreover, the provision of this requirement is mandatory for all the main participants in the construction process: the developer, the technical customer, the person providing or preparing the investment justification, or the person responsible for the operation of the facility.
Also, other regulatory documents were previously published, the adoption of which is focused on the development of information modeling of buildings and structures in Russia: x Decree of the Russian Federation Government of September 15, 2020 No. 1431, which approved the rules for the formation and maintenance of the information model, the composition of information, documents and materials included in the information model and presented in the form of electronic documents, requirements for the formats of these electronic documents.
x The Order of the Ministry of Construction of Russia dated December 24, 2020 No. 854 / pr, which approved the methodology for determining the cost of work on the preparation of project documentation containing materials in the form of an information model. There is a list of set of rules that are relevant for Russia (as of March 2021) describing the requirements for the implementation of projects using information modeling technologies in construction below: 1. SR 301.1325800.2017 "Information modeling in construction. Rules for the organization of work by production and technical departments " 2. SR 328.1325800.2017 "Information modeling in construction. Rules for describing information model components." 3. SR 331.1325800.2017 "Information modeling in construction. Exchange rules between information models of objects and models used in software systems." 4. SR 333.1325800.2017 "Information modeling in construction. Rules for the formation of an information model of objects at various stages of the life cycle " 5. SR 404.1325800.2018 "Information modeling in construction. Rules for the development of project plans implemented using information modeling technology." 6. SR 471.1325800.2019 "Information modeling in construction. Quality control of construction works." 7. SR 480.1325800.2020 "Information modeling in construction. Requirements for the formation of information models of capital construction objects for the operation of apartment buildings implemented under reuse projects." 8. SR 481.1325800.2020 "Information modeling in construction. Rules of application in cost-effective design documentation for reuse and when it is linked." It is important to note that the regulatory support of information modeling in Russia is built around the concept of an information model, as a set of files containing a certain set of data that meets certain requirements in terms of format and name. At the same time, according to ISO 19650-1: 2018, the information modeling of the EU countries is built around the concept of an "information container", which allows software developers and project participants not to be tied to the file data structure, but to build information modeling processes directly around the data, and not how they storage and transmission.
At the same time, it is obvious that the development of a system of state regulation of information modeling should also be accompanied by the development of a system of internal regulation and standardization of the use of BIM at the level of companies that are customers of services for the development and implementation of construction projects.

Basic approaches to ensuring data interoperability
City Geography Markup Languages (CityGML), Shape (SHP) and Industry Foundation Class (IFC) are the three most popular data exchange formats for mutual integration in Geographic Information System (GIS) and Building Information Modeling (BIM) projects [40].
At the same time, compatibility problems between them are noted, the main of which is the loss of data in the process of information transformation.
On the one hand, GIS is georeferenced topological data that allows to perform spatial analysis of the described objects, as well as to solve problems related to the optimization of paths, position and determination of the zones of influence of objects. On the other hand, BIM is not capable of such analysis, but its essence is the formation of a detailed database of object-oriented parametric information for structures and buildings, closely related to the three-dimensional model [41,42].
During transferring information between BIM and GIS formats, the key issues are the issues of ensuring the completeness and reliability of geometric transformations, as well as the semantic transfer of information. For BIM, the representative data format is IFC, an open object-oriented data format. There are two main formats available for GIS: CityGML and Shapefile (SHP). At the same time, it is SHP that is used in applied projects, since has the property of storing parametric information, and is better suited for BIM and GIS integration.
Researchers note that the mutual integration of BIM and GIS can provide a deeper understanding of the processes accompanying the construction of facilities, which ultimately affects the quality and speed of decisions made both at the design stage and at the stages of direct construction of facilities [43]. Such integration allows to effectively manage information at the design, construction and operation stages, thus capturing all stages of the object's life cycle.
The main system for dividing the levels of integration of BIM and GIS is the division into three groups [44]: x Data level. At this level, models and data formats are manipulated (transformed) to meet the requirements of the application used in the project. Such an approach is effective in the degree of adaptation of requirements to a specific project, but does not have the ability to scale and develop outside the framework of a specific or similar project; x Application level. This level implements the new applications that provide the functionality integration of BIM and GIS. At the same time, the level of mutual penetration of BIM and GIS is dictated only by the needs of the project, but limited by the capabilities of the applications used; x Process level. At this level, both BIM and GIS are involved in the workflow and are integrated. It is difficult to achieve the last two levels today [44], and special attention at the current stage of development of mutual integration of BIM and GIS systems should be paid to the first level and the development of tools for its implementation. This is due, among other things, to the fact that the fundamental problems of the loss of semantic information because of the integration of BIM and GIS have not yet been resolved, the solution of which is seen only in the modification of the formats themselves to the requirements of a particular project, although in the future the focus of solving this problem will shift to the area development of universal data formats capable of lossless integration of BIM and GIS.

Results
Considering all the above, it can be concluded that the development of the transport infrastructure of regions and countries soon is inextricably linked with the introduction and application of information modeling technologies at all stages of the life cycle of transport infrastructure objects.
At the same time, the need for the transformation and development of today's formats for the exchange and storage of design data is clearly expressed. A promising solution in this area is the development of the mutual integration of formats, as well as the platforms that support their use, IFC and SHP, which, in combination with each other, provide a description of many geometric parameters of a project for wide geographic scales, as well as a full-fledged parametric filling of models.
At the same time, the software systems used for the implementation of information modeling of transport infrastructure objects remain a subject for discussion, since none of the software systems on the market today provides the functionality of work that fully satisfies all market participants, as well as the level of interoperability, requirements for which are critical in the context of integrating BIM and GIS formats with the need to preserve the benefits of both. Bentley Systems has received the best endorsements from users and companies on the market.
The considered experience of the widespread implementation of information modeling in the construction of transport infrastructure in various countries and companies allowed the authors of the study to identify several key points on the way of introducing this technology: • The basis for the implementation and development of the use of information modeling technologies for transport infrastructure facilities at the company level should be a structural transformation in the project department associated with the emergence of the position of a BIM manager, whose responsibilities should include organizing and coordinating the joint work of project department employees with the allocation of targets for retraining and professional development of employees with the aim of a gradual transition from 2D CAD-modeling to 3D + BIM-modeling; • The main incentive for the introduction of information modeling technologies for transport infrastructure objects should be the emergence of BIM standards (and at the company level -EIR, which are a mandatory annex to the technical task), containing a detailed set of requirements for design data (including their structure and transfer formats between stages project implementations); • At the country level, it is necessary to ensure the implementation of educational programs based on secondary specialized and higher educational institutions, as well as programs for retraining and advanced training for specialists implementing projects using information modeling technologies for transport infrastructure facilities.

Discussion
Based on this study, the authors present the development of information modeling technologies for transport infrastructure in Russia as a process of close interaction between E3S Web of Conferences 263, 05029 (2021) FORM-2021 https://doi.org/10.1051/e3sconf/202126305029 the state, companies performing the functions of a customer, executing companies in the design sphere, executing companies in the field of construction, as well as companies operating buildings and structures. The authors are convinced that the phased implementation of BIM technologies in relation to the functional levels of project activities, as well as to process events during the implementation of the project, is a criterion for the sustainable development of digital construction in the field of transport infrastructure.
The authors will direct their further research for detailing the key stages of the implementation of the transition to information modeling of transport infrastructure facilities, including determining the influencing factors on the possibility and level of implementation of a full-fledged monitoring system for these facilities using distributed sensor systems, collection and processing of big data based on BIM-models.
The reported study was funded by RFBR, Sirius University of Science and Technology, JSC Russian Railways and Educational Fund "Talent and success", project number 20-38-51013