Editorial for “Sustainable and Digital Transformation of Road Infrastructures”

Road infrastructure is increasingly recognized as a critical asset for economic development, social cohesion, and territorial connectivity. However, it is under unprecedented pressure from climate change, resource scarcity, environmental constraints, and rapidly evolving societal expectations. Traditional construction materials, design approaches, and maintenance practices—mostly dependent on non-renewable resources and periodic inspections—are increasingly recognized as insufficient to ensure the long-term sustainability, resilience, and efficiency of road networks [1]. As a result, the transformation of road infrastructure is now widely understood to be a dual process in which sustainability and digitalization must evolve together rather than independently or sequentially [2].

Recent research has focused on reducing the environmental footprint of road construction and maintenance by adopting circular economy principles, using renewable or waste-derived materials, and optimizing life-cycle performance [3,4]. As a result, there is a growing amount of attention being paid to bio-based binders, alternative aggregates, recycled materials, and innovative mix designs to reduce dependence on petroleum-based products and minimize greenhouse gas emissions. These approaches are increasingly supported by experimental and field evidence, showing that environmental benefits can be achieved without compromising performance, durability, or safety [5,6]. The relevance of these developments is reinforced by broader concerns about bio-sustainability, biodiversity protection, and the responsible use of natural resources within transport infrastructure systems [7].

Climate change has emerged as a significant challenge with respect to the performance of road infrastructure. Increased temperature variability, more frequent extreme-weather events, and altered loading conditions require pavement structures and materials that can maintain functionality in more aggressive and uncertain environments. Recent studies have focused on performance-based design, advanced material characterization, and resilience-oriented assessment frameworks that explicitly account for climatic effects throughout the infrastructure life cycle [8,9]. These advances can help give rise to more robust design decisions, extend service life, and reduce long-term maintenance and adaptation costs.

Alongside material and structural innovation, the digital transformation of road infrastructure is rapidly reshaping how assets are monitored, managed, and maintained. Advances in sensing technologies, data acquisition systems, and communication networks enable the continuous collection of large volumes of data on traffic, environmental conditions, and structural responses [10]. When combined with artificial intelligence, machine learning, and advanced data analytics, these technologies support a shift from reactive to predictive and preventive maintenance strategies, improving resource efficiency and enhancing the long-term performance of road assets [11,12].

Recent advances in automated inspection, computer vision, and intelligent monitoring systems further illustrate this transition. Applications such as image-based distress detection, connected-vehicle data, fiber-optic sensing, and remote inspection platforms demonstrate how digital tools can enhance safety, reduce inspection costs, and increase temporal and spatial resolution in infrastructure condition assessment [13,14]. Notably, these approaches directly contribute to sustainability objectives by optimizing maintenance interventions, reducing unnecessary material consumption, and minimizing traffic disruptions throughout infrastructure’s life cycle.

From a broader perspective, the transformation of road infrastructure is closely tied to ongoing shifts in mobility and energy. The electrification of transport, particularly in freight corridors, requires integrated planning to align road infrastructure development with energy supply, charging infrastructure deployment, and traffic demand [15]. This need highlights the growing interdisciplinary nature of road infrastructure research, integrating materials engineering, data science, transportation planning, and energy systems.

More recently, the concept of digital twins has gained prominence as a unifying framework for infrastructure management. By integrating sensing, modeling, simulation, and decision-support tools into a single digital environment, digital twins lead to more informed, transparent, and adaptive management strategies [16,17]. Within the broader vision of Construction 5.0, these approaches emphasize not only efficiency and automation but also resilience, sustainability, and human-centered decision-making.

Beyond technological and material innovation, the effective implementation of sustainable and digital road infrastructure increasingly depends on broader institutional and societal frameworks. Public procurement, standardization, and technical specifications, as key enablers of change, have recently been attracting an increasing amount of attention. Moving beyond decision-making processes that are predominantly based on initial cost or isolated performance indicators, there is a clear need for more holistic assessment frameworks that explicitly value durability, life-cycle performance, resilience to climate change, circularity, recyclability, and environmental protection, including biodiversity considerations. Such approaches also create opportunities for innovation-driven markets, skill development, and new forms of employment, reinforcing the societal dimension of infrastructure sustainability [18]. While these aspects were not the primary focus of this Special Issue, they are essential conditions for translating scientific advances in sustainability and digitalization into real-world impacts and long-term public value.

In parallel, emerging modeling approaches at the molecular scale are beginning to provide deeper insight into aging mechanisms, material interactions, and durability phenomena in paving materials. Although still in the early stages of practical application, these approaches offer promising pathways to explaining how processes at the microscale influence macroscopic performance, surface characteristics, and long-term behavior, thereby supporting the development of more durable, sustainable, and resilient materials [19,20]. Such perspectives are expected to become increasingly relevant in future research.

The themes addressed in this Special Issue align closely with current international research agendas and policy frameworks. European strategies, including the Green Deal, the Circular Economy Action Plan, and the Sustainable and Smart Mobility Strategy [21,22], along with global perspectives from organizations such as the World Bank, OECD, PIARC, and FHWA, consistently emphasize the need for sustainable, resilient, and digitally enabled transport infrastructure [23,24,25,26,27]. The recent launch of the HORIZON-CL5-2026-01-D6-07 call further confirms the strategic relevance and timeliness of research on the sustainable and digital transformation of road infrastructure [28].

The contributions collected in this Special Issue reflect these broader trends and offer concrete examples of how research is addressing pressing global challenges. The authors of recent studies have advanced sustainable pavement materials by developing bio-based binders and incorporating alternative or recycled constituents, thereby reducing environmental impacts while maintaining functional performance [29,30]. In parallel, other contributions have demonstrated how digital technologies—such as embedded sensing systems, data-driven monitoring, and artificial intelligence—enable more efficient, scalable, and predictive approaches to infrastructure condition assessment and maintenance [31,32]. At a more integrative level, the inclusion of a review on cognitive digital twins within the Construction 5.0 paradigm highlights how sustainability, digitalization, and human-centered decision-making can be jointly addressed in road infrastructure management [33]. Collectively, these contributions reinforce the view that future progress in road infrastructure engineering will depend on integrating sustainability principles, digital technologies, life-cycle thinking, climate resilience, and societal considerations. Thus, this Special Issue offers a snapshot of an evolving research landscape rather than a closed body of work.

Given the pace of technological development and the ongoing urgency of sustainability and climate challenges, the editors anticipate that these themes will remain highly relevant in the near future. Preparing a second edition of this Special Issue is therefore timely, offering an opportunity to capture emerging advances, particularly in areas such as biosustainable materials, digital twins, resilience assessment, societal impact evaluation, and data-driven infrastructure management.

The editors are grateful to the authors for their contributions, the reviewers for their thorough and helpful feedback, and the Infrastructures editorial team for their support. We hope that this Special Issue will advance research, policy, and practice in road infrastructure toward greater sustainability, digital intelligence, and resilience.