Advancing Sustainable Concrete Materials and Resilient Structures

1. Introduction

This editorial posits that the defining challenge for 21st-century civil engineering is the synthesis of two historically distinct goals: environmental sustainability and structural resilience. Arguably, these are not competing priorities but rather two faces of the same coin, integral to the creation of infrastructure that is reliable, resilient, robust, and in harmony with our planet. Global cement manufacturing, a cornerstone of modern society, stands at a critical juncture, facing immense pressure to reduce its significant carbon footprint, while our aging infrastructure must be fortified against escalating climate-driven hazards. This editorial begins by outlining the urgent need for change in global infrastructure, followed by a summary of the main findings from the papers featured in this Special Issue. Then, it presents a forward-looking vision for a new generation of materials and structures that are not only low carbon but also intelligent, adaptive, and self-healing. Subsequently, it serves as a formal Call for Papers for the second volume of this Special Issue, inviting the global research community to contribute novel and innovative work that will turn this vision into reality.

It is with immense pleasure that I introduce this volume, a comprehensive collection of innovative research, originally presented as a Special Issue in Applied Sciences. This work brings together a diverse array of studies that collectively advance our understanding and capabilities in the critical areas of sustainable concrete materials and the design and assessment of resilient structures. In the face of contemporary economic, social, and environmental challenges, the construction industry is continually driven to innovate, seeking solutions that enhance resilience, reduce costs, and simplify maintenance while mitigating its significant environmental impact [1]. This volume serves as a vital resource for academics, researchers, graduate students, and industry professionals navigating these evolving demands.

2. The Need for Transformation: Global Infrastructure at a Crossroads

As a global community of engineers, scientists, and builders, we are the architects of the modern world. The very fabric of our civilization—our cities, transport networks, and shelters—is built upon material of our own making: cement and concrete. Yet, we must now confront the profound consequences of our success. Let us begin with an uncomfortable fact about our current reality: the worldwide yearly production of concrete is projected to increase from 14 billion cubic meters today to 20 billion cubic meters by the middle of the century, driven by urbanization and rising infrastructure needs [2]. This annual production has built our world, but it has come at a staggering environmental cost. Figure 1 demonstrates that cement production, once a minor source of emissions, has become a significant contributor to global CO₂ levels, underscoring the link between economic development, construction activity, and climate impact. Without intervention, this upward trajectory suggests cement will continue to be a major challenge for decarbonization efforts.

The reliance on Portland cement, an excellent binder, yet one whose creation is both energy- and carbon-intensive, is fundamentally unsustainable at its current scale and trajectory.

This urgency for transformation is further driven by the intensifying climate crisis, with global warming projected to exceed the critical 1.5 °C threshold without immediate reductions [3,4,5]. The crisis of resources is now colliding with a crisis of risk, creating a perfect storm for our built environment. The increasing frequency and intensity of hurricanes, floods, wildfires, and seismic events expose the deep vulnerabilities of legacy infrastructure [6]. These structures were often excellently engineered in light of the static historical climate data of a world that no longer exists. The traditional focus on singular metrics such as concrete compressive strength or prescriptive code-based detailing, while foundational to safety, is proving insufficient to ensure functional continuity and rapid recovery in the face of these new, dynamic, and often concurrent threats.

It is from this critical point that it is important to realize the prevailing design philosophies, where materials are inert, structures are passive, and lifecycles are linear, are inadequate. The economic and environmental extravagance of building disposable infrastructure, designed only to be demolished and replaced, can no longer be afforded. This moment of challenge, however, is also a moment of opportunity. It compels us to move beyond incremental adjustments and, instead, fundamentally rethink how we design, what we build with, and the very nature of the legacy we leave for generations to come. The imperative for change is not a distant concern; it is here, and it demands our immediate and collective ingenuity.

3. Development of Sustainable and Resilient Infrastructure

The papers in this collection exemplify the multidisciplinary efforts underway to address the need for transformation for concrete construction. They address four key themes crucial for the development of sustainable and resilient infrastructure:

• Theme 1: innovative manufacturing and material optimization

A significant thrust in modern construction involves the adoption of advanced manufacturing techniques and novel material compositions. Additive manufacturing (3D concrete printing) is a prime example, offering flexibility in material selection and geometric forms and high customization [7]. For 3D-printed concrete to be widely adopted, robust quality control is essential. A non-destructive method has been developed to verify the on-site compressive strength of printed elements, which avoids the need for destructive core sampling [8].

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Theme 2: enhancing structural resilience and durability through advanced composites

Carbon fiber-reinforced polymer (CFRP) is a highly effective material for enhancing the resilience of concrete structures, particularly against seismic loads or environmental degradation [9]. Its high strength, durability, and corrosion resistance make it ideal for retrofitting. For instance, applying CFRP to beam–column joints can strategically relocate potential failure zones, known as plastic hinges, from the vulnerable joint to the stronger beam section. This significantly boosts the connection’s capacity and the structure’s overall seismic performance. Additionally, wrapping concrete elements with CFRP provides powerful confinement. This technique can dramatically increase the compressive strength and ductility.

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Theme 3: sustainable material sourcing and waste utilization

A key aspect of sustainability in concrete is the reduction in its environmental footprint, particularly that associated with cement production [10]. The performance of concrete can be enhanced through the strategic addition of waste materials [11]. Research in this collection indicates that using glass flour as a 10% substitute for traditional cement not only reduces the clinker content but also boosts the final product’s compressive strength [12]. Adding polypropylene fibers to this formulation further improves its resilience, creating a composite capable of withstanding negative temperatures. This method provides a pathway to high-performance concrete while simultaneously achieving environmental goals such as waste reduction and lower emissions.

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Theme 4: life cycle assessment and advanced predictive modeling

Understanding the full environmental and economic impacts of concrete structures is crucial for truly sustainable design. A life cycle analysis of large concrete structures reveals that cement production is the primary source of carbon emissions, but recycling demolished concrete can significantly cut these emissions [13]. This benefit often outweighs the slightly higher demolition costs and must be balanced against design choices, where stronger concrete reduces the material volume but increases emissions due to its higher cement content.

The collective body of work presented herein reflects the dynamic and innovative spirit within the field of concrete engineering. It shows diverse approaches to tackling the complex challenges of modern construction, from developing materials with reduced environmental footprints to enhancing the longevity and resilience of vital infrastructure. The reflections within this volume will undoubtedly inspire further research, foster interdisciplinary collaboration, and accelerate the adoption of sustainable and resilient practices in the global construction industry.

4. A Forward-Looking Vision: The Next Generation of Reliable, Resilient, and Robust Infrastructure

Having achieved significant progress and established the urgent need for a new path, it is time now to turn from the problems of the present to the possibilities of the future. Our vision is not one of incremental improvement but of a shift in principle as to how we conceive of our fundamental building materials and the structures they form. It is essential to move beyond the passive and inert and begin to engineer materials and systems with integrated life-like functionalities.

First, it is envisioned that the next frontier of concrete is not a static material but one with a metabolism. Imagine concrete that actively contributes to environmental remediation by sequestering atmospheric CO₂ through advanced mineral carbonation, effectively turning our buildings and bridges into carbon sinks [14,15]. Picture bio-inspired concretes with internal vascular networks, analogous to a biological circulatory system, that can transport healing agents to autonomously repair microcracks as they form [16,17]. This would dramatically extend the service life, enhance the durability, and eliminate the cycle of costly carbon-intensive manual repairs, creating structures that heal instead of degrading.

Second, the future of resilience lies in creating a sentient structure. The infrastructure could be integrated with dense networks of self-powered sensors, from embedded fiber optics to piezoelectric nano-sensors, that function as a coherent nervous system [18,19,20]. This system would continuously stream data to a high-fidelity “digital twin”, a dynamic virtual model that evolves with its physical counterpart [21,22]. This would allow for predictive health monitoring and real-time performance assessment during an extreme event, but more importantly, it would enable adaptive responses. A bridge could detect the unique vibrational signature of an approaching seismic shockwave and trigger actuators to momentarily stiffen key structural members, actively mitigating damage before it occurs.

Third, as we look ahead, critical areas for continued investigation include the broader validation of new materials and methods across various environmental conditions and scales, more in-depth analyses of chemical interactions and long-term durability, and the further integration of advanced computational tools such as machine learning for real-time monitoring and optimization [23,24,25].

This vision is achievable only through the synergy of the digital and the physical. The discovery of novel low-carbon binder chemistries will be radically accelerated by artificial intelligence (AI) and machine learning (ML), allowing us to navigate vast compositional spaces and move beyond laborious trial-and-error experimentation. Concurrently, advanced manufacturing, such as robotic 3D printing, will liberate us from the constraints of conventional formwork. This will enable the creation of structurally optimized and materially efficient geometries that place strength and function precisely where needed, integrating multi-functionality directly into the structural form and heralding a new era of architectural and engineering creativity.

5. The Call to Action: Announcing the Second Special Issue

The concepts outlined above are not distant dreams; their foundational elements are emerging from laboratories around the globe at this very moment. To accelerate this critical transition from laboratory potential to field-deployed reality and to foster the cross-disciplinary collaboration this work demands, we are proud to announce the Call for Papers for Volume II of our Special Issue on “Sustainable Concrete Materials and Resilient Structures”.

This is a direct challenge to the community. We seek contributions that transcend incremental improvements and instead redefine the boundaries of what is possible. We challenge our colleagues to submit their most ambitious boundary-pushing research that directly addresses the integration of sustainability and resilience. We are particularly interested in work that demonstrates a clear and viable pathway from fundamental scientific discovery to transformative engineering application.

While we welcome all innovative work in this area, we are especially encouraging submissions that focus on the following high-interest topics:

• Next-Generation Binders and Systems: research on non-Portland systems such as geopolymers, alkali-activated materials, magnesium-based cements, and calcined clay–limestone (LC3) systems with demonstrated low-carbon footprints and robust durability performance.
• The Circular Economy in Practice: advanced research on the valorization of complex industrial and post-consumer waste streams as high-value aggregates and supplementary cementitious materials, including comprehensive life cycle assessments that validate their net environmental benefit.
• Multi-Scale Mechanics of Resilience: novel experimental and computational studies that link material micro-mechanisms of damage and healing to the macro-scale performance and fragility of entire structural systems under multi-hazard conditions.
• Sensing, Monitoring, and Adaptation: papers detailing innovative sensing technologies for embedded structural health monitoring (SHM), data fusion techniques for creating high-fidelity digital twins, and proof-of-concept studies of adaptive structural components.
• Innovative Case Studies: real-world or large-scale laboratory case studies of structures designed and built with an explicit quantifiable integration of sustainability and resilience metrics, providing invaluable data and lessons for the broader community.

6. Concluding Remarks: Building Tomorrow’s Legacy, Together

The path forward requires a radical reimagining of the boundaries of our disciplines. The challenges of decarbonization and resilience are far too complex for any single field to solve in isolation. Unprecedented collaboration between materials scientists, structural engineers, architects, data scientists, and policymakers is not just beneficial; it is essential. It is critical to foster an ecosystem of innovation, where a breakthrough in binder chemistry can seamlessly inform a new parameter in a structural design model, and where policy enables, rather than hinders, the adoption of these next-generation solutions.

This Special Issue and the continuing work it represents is more than an academic exercise. It is a collective commitment to our professional and societal responsibility to provide the safe, enduring, and environmentally harmonious infrastructure that future generations deserve. The papers we publish, the research we conduct, and the students we mentor are all cornerstones of this new edifice.

The blueprint for the future is unwritten, and the materials are waiting to be invented. Let us, together, answer this call and begin the vital work of engineering the legacy of tomorrow.