The collapse of the “Carolabrücke” in Dresden has brought the issue of stress corrosion cracking and its risks to infrastructure into sharp focus. This special session will discuss the findings regarding the damage mechanisms and the investigative approaches applied to the structure. Other key topics include options for ensuring safe ongoing operation, such as monitoring systems or structural reinforcements.

Planned as Inspirative Lecture Session.

The construction industry has made real strides in reducing concrete’s carbon foot-print — through wider adoption of supplementary cementitious materials, and alkali-activated binder systems. But sustainability gains can go further: using less concrete per structure, achieved through geometrically optimized designs that place material only where it is structurally needed. Such forms, however, push conventional construction methods to their limits. Digital fabrication changes that equation entirely. This special session gathers leading experts to examine how digital fabrication can serve as a genuine engine of sustainable construction. Discussions will span low-carbon formulations for printable concretes, rheology-driven process optimization, structural efficiency through freeform and topology-optimized geometries, lifecycle assessment, circular economy strategies, and AI-assisted quality control for waste minimization.

The goal: Consolidate today’s knowledge, identify critical research gaps, and define a shared roadmap for making digital fabrication a cornerstone of sustainable building practice.

Assessing the serviceability and safety of reinforced concrete structures increasingly relies on numerical modeling. However, the nonlinear behavior of reinforced concrete means that linear-elastic FEM is often insufficient, while advanced non-linear FEM can be computationally demanding, time-consuming, and prone to numerical instability. This special session invites contributions on design-oriented analysis methods that bridge the gap between overly simplified models and highly specialized non-linear simulations. The focus is on practical, efficient, and robust approaches that enable engineers to evaluate the behavior and capacity of reinforced concrete structures with limited modeling effort and computational cost. Topics may include

• stress-field methods,
• optimization-based analysis,
• simplified non-linear modelling strategies,
• and related approaches

for the practical assessment and design of reinforced concrete structures.

This special session aims to rethink reinforcement strategies for 3D concrete printing by exploring hybrid or composite approaches based on additive manufacturing that combine cementitious materials printing with metal, polymeric, fiber-based reinforcing systems. While 3DCP enables formwork-free and digitally controlled construction, the integration of reinforcement, ductility, robustness, and reliable load transfer remains a key challenge for structural applications. The session will address additive and digitally fabricated reinforcement solutions, including

• metallic reinforcement produced by WAAM or related techniques,
• polymeric and fiber-reinforced inserts,
• printed connectors,
• composite or compound wall systems,
• and post-integrated reinforcement concepts.

Contributions are expected to discuss technological feasibility, mechanical performance, interface behavior, bond and anchorage, durability, sustainability, and design implications. The session intends to bridge material innovation, structural mechanics, digital fabrication, and life-cycle considerations, promoting new concepts for reinforced and ductile 3D printed concrete structures.

In the context of sustainable construction and circular economy principles, this session invites contributions focusing on the extension of service life and structural reuse through hybrid structures combining concrete, timber, and/or steel as well as strengthening techniques using fiber reinforced polymer (FRP) materials.

The session emphasizes three key objectives:

1. hybrid and composite structures combining concrete, timber, steel, or FRPs, and assessment of their mechanical capacity through experimental or numerical methods;
2. extending the service life of structural elements through advanced strengthening and reinforcement techniques;
3. enabling structural reuse by enhancing the robustness, adaptability, and demountability of connections.

Contributions are encouraged on topics including composite structures combining major construction materials, advanced strengthening approaches such as the use of FRPs for both primary elements and connections, innovative connection systems that facilitate flexibility and reuse, and multi-scale, multi-physics modeling frameworks to accurately predict composite behavior and structural interactions.

This special session focuses on advancing quality control and performance evaluation for additively manufactured cementitious composites, notably 3D concrete printing (3DCP). While 3DCP offers unparalleled architectural flexibility and sustainability, it introduces distinct microstructural complexities like material anisotropy, localized print defects, and early-age structural variations. To ensure long-term structural integrity and support widespread industrial-scale adoption, robust quality assurance frameworks are crucial.

This session explicitly addresses the deployment of advanced non-destructive testing (NDT) and evaluation methodologies, by focusing on feasibility of innovating data-driven instrumentation and data analysis protocols for tracking material evolution, processing conditions, print-process variations, and post-printing characteristics, aiming to achieve higher cost-efficiency of the manufacturing process and strategic mitigation of structural failures due to subpar quality. The session aspires to gather leading global researchers, engineers, and practitioners to discuss standardized protocols, real-time monitoring strategies, and material characterization, bridging the critical gap between digital fabrication and reliable structural engineering.

Planned as Inspirative Lecture Session.

This special session explores the structural performance and application potential of 3D-printed concrete (3DPC), focusing on both experimental advances and material innovations. As digital fabrication technologies mature, understanding the mechanical response of printed elements, especially in demanding applications (extreme loading events), is vital. The session includes studies on load-bearing behavior of 3D printed concrete under high impact loading, mechanical and bond performance between cast and 3D printed concrete, and structural optimization of 3D printed concrete structures.

Composite dowel connectors are increasingly used to achieve efficient transfer of longitudinal shear forces for the interface between steel and concrete to realize composite action and structural integration in modern construction. Owing to their simplicity, robustness, and excellent mechanical performance, they have been applied in steel–concrete, steel-timber–concrete, steel–UHPFRC, hybrid, modular, prefabricated, and fatigue-resistant structures. Recent developments further highlight their potential for sustainable and circular construction, including recycled, low-carbon, and high-performance materials.

This special session aims to bring together researchers, engineers, and industry professionals to exchange recent advances in composite dowel connector systems and related connection technologies. Contributions are welcome on experimental, numerical, and analytical studies of composite dowel connectors and related connection technologies, including load-transfer mechanisms, interface behaviour, composite action, fatigue and seismic performance, durability, reliability-based design, sustainability assessment, design recommendations, and practical engineering applications. The session seeks to promote interdisciplinary discussion on innovative, sustainable, and resilient structural systems.