4.3.1 Introduction

In recent years, digitalization in the construction industry has been accompanied by the term “BIM” (Building Information Modeling). Most practitioners associate BIM with the planning, design, and construction of vertical infrastructure and occasionally with tunnels or bridges. More recently, BIM methods are being applied to horizontal infrastructure.

The term “horizontal infrastructure” is used to describe the entire infrastructure networks, such as roads, railroads, water supply and sewage, telecom, diverse pipelines, etc., under the responsibility of one operator or owner. Horizontal infrastructure consists of linear infrastructure objects, such as road sections, and objects of other types, such as bridges, parking, toll stations or road equipment facilities. The subject of the operational phase of asset management is usually the entire horizontal infrastructure.

The implementations of BIM to date have focused on buildings and, in the road sector, on engineering structures such as bridges, tunnels, complex traffic intersections and sometimes on single linear infrastructures such road sections. At the same time, there are still very few solutions that address overall horizontal infrastructures, such as road networks. The horizontal infrastructures have so far only been accompanied by BIM processes during the planning or construction of their single components. This limitation of BIM to specific design and construction projects ignores the fact that, from the perspective of the operator of the horizontal infrastructure, the entire network, e.g. the national or regional road network, is often the subject of consideration and operational activity.

Such tasks as prediction of maintenance demand in order to achieve specific quality goals, preparation of maintenance programs, or network-related resilience analyses can only be performed successfully if certain information is only available across the entire network. This information must be available at the appropriate quality from the operator's perspective in terms of accuracy, completeness, and timeliness to support its tasks. In the road sector, such data primarily includes as-built data, condition data and traffic data. They are managed in the road information databases maintained by the operators for a particular road network.

Recent experience has demonstrated that the implementation of BIM processes can contribute to an increase in the efficiency of the planning, designing and construction of all transportation infrastructures. Time and cost discipline increases and the risks for owners, designers, constructors and suppliers are reduced.

The use of BIM in the transportation sector is becoming more mature and standards and best practice procedures have been developed, partly thanks to considerable government funding projects, and the software companies providing easy to use tools and applications. The experience gained using BIM is now being presented and exchanged at international meetings, conferences and through non-profit organizations such as buildingSMART or National Institute of Building Sciences (NIBS). PIARC has also contributed to the dissemination of BIM techniques for the road sector. In the report "BIM and Digitalization" (PIARC 2023), the fundamental rules for the application of BIM for infrastructure projects were presented through the publication of BIM case studies.

Owners and operators of horizontal infrastructure, such as runways, roads or railroads, also benefit from the adoption of BIM systems. Typically, these include local and central governments as well as private or public operators of infrastructure systems. The current focus of BIM is at the design and construction phase, and it does not sufficiently support the management and operation needs of transportation infrastructure on the network level.  This shortcoming of BIM is now increasingly being addressed in various publications

In contrast to planning and construction companies that focus on individual projects, the manager of horizontal infrastructure is responsible for the ongoing management of an entire infrastructure system, or in many cases, the entire infrastructure portfolio. This typically includes inventory, construction and maintenance history data, asset condition, past, present and future traffic information etc. They all contribute to the Asset Information Model of the infrastructure portfolio. The requirements for the Asset Information Model must be defined in such a way that all operational obligations to keep the certain level of service are met in a sustainable manner. In addition to the direct operational tasks, the measures for asset maintenance and upgrading should also be planned and implemented. Maintenance and renewal decisions requires the consideration of needs of the entire network.

The specification of the requirements for the Asset Information Model, i.e. the data of the entire asset system or asset portfolio, is one of the relevant decisions to be made by the owner or operator of an infrastructure network. The requirements for the Asset Information Model are thus always a compromise between the desired high level of detail (high data quality) and ensuring that all data is available in the required completeness and timeliness. To ensure this in a sustainable way, the model must be aligned with the maturity of the organization and the goals of the infrastructure owner.

In recent years, BIM has moved forward to support the operational phase of asset management. The ISO 19650:2018 (ISO 2018) standard plays a key role in this context, positioning BIM in the direct environment of Asset Management in accordance with ISO 55000:2014 (ISO, 2014). Both standards are primarily focused on asset managers. ISO 55000 is considered a relevant guide for the present Road Asset Management Manual of PIARC. The requirements for information models, in the operational phase (Asset Information Models), and in the project phase (Project Information Models) in the ISO 19650 (ISO, 2018) standard are formulated in such a way that they can also be applied to Road Asset Management and to other horizontal infrastructure. This provides favourable opportunities for a broader digitalization that extends to the entire network and not only to the individual projects.

The present section of the manual deals with the most relevant aspects of digitalization and information management from the point of view of the owner and operator of the road infrastructure. It is strictly oriented to the ISO 19650 standard while addressing the context of the entire road network. For the aspects of BIM and digitalization at the project level, please refer to the above-mentioned PIARC report (PIARC, 2023).