Special Sessions

Organizers: Luciano Ombres (University of Calabria), Pietro Mazzuca (University of Calabria), Tomasz Trapko (Wrocław University of Science and Technology)

The need for efficient and durable strengthening solutions for existing reinforced concrete (RC) and masonry structures has become increasingly pressing due to aging infrastructure, evolving design codes, and increased seismic demands. Fabric Reinforced Cementitious Mortar (FRCM) composites, have emerged as a promising class of materials offering high mechanical performance, compatibility with existing substrates and ease of application.

This special session aims to gather and promote cutting-edge research on the application of FRCMs for structural strengthening and retrofitting. Contributions are encouraged in the form of theoretical studies, numerical modeling, and experimental investigations. Topics of interest include, but are not limited to: bond behavior between FRCMs and substrates, out-of-plane and in-plane strengthening of masonry walls, flexural and shear strengthening of RC elements, long-term performance and durability, hybrid strengthening systems, and case studies of real-world applications.

The session will provide a platform for interdisciplinary dialogue among academics, engineers, and practitioners, fostering the development of innovative solutions and standardization efforts. Emphasis will be placed on both fundamental research and the translation of scientific knowledge into practical engineering approaches.

By addressing the challenges and opportunities associated with FRCM-based strengthening techniques, this session contributes to the sustainable preservation and seismic resilience of the built environment.

Organizers: Bernhard Schranz (Sika AG), Yunus Emre Harmanci (Empa)

As the construction industry transitions toward circular economy principles, fiber-reinforced polymers (FRPs) offer significant potential not only for structural performance but also for advancing sustainability goals. This special session will explore the evolving role of FRP systems in enabling circular construction through innovations in material durability, sustainable design, and reuse strategies.

With a focus on both new and applied research, the session invites contributions that address the full lifecycle performance of FRP systems and retrofitted buildings. Topics of interest include but are not limited to: development of reversible bonding technologies, “debonding on demand” mechanisms, design for disassembly, novel bonding and installation techniques, new materials, low-impact fibers and resins, and case studies on the impact of FRPs on the complete building life-cycle. Emerging evaluation and monitoring techniques that support decision-making around these topics will also be covered.

The session aims to connect material scientists, structural engineers, and industry practitioners to foster dialogue around novel approaches and practical solutions that align with global climate and resource efficiency targets. Contributions that bridge experimental research with implementation, especially in retrofit and infrastructure renewal contexts, are particularly encouraged.

By reframing FRP applications through the lens of circularity, this session offers a platform to showcase how advanced composite systems can support the transformation toward more sustainable, resilient, and future-ready built environments.

Organizers: Raafat El-Hacha (University of Calgary), Amir Fam (Queen's University)

This special session is dedicated to celebrating the outstanding contributions of Dr. Sami Rizkalla to the field of fiber-reinforced polymers (FRP) in civil infrastructure. Over the past four decades, Dr. Rizkalla has played a pivotal role in pioneering research, advancing design methodologies, and fostering international collaboration in the development and application of FRP composites in structural engineering. His leadership within the FRPRCS community, including co-founding and chairing numerous international committees, has left an enduring impact on research, education, and practice.

The session will bring together leading academics, researchers, practitioners, and former students whose work has been influenced or inspired by Dr. Rizkalla’s legacy. Topics will span a wide range of FRP-related themes including: shear and flexural behaviour of FRP-reinforced concrete elements, strengthening and retrofitting techniques using externally bonded and near-surface mounted FRPs, bond behaviour and anchorage, durability of FRP materials, and the development of design guidelines and code provisions.

The session aims to foster technical exchange, recognize past achievements, and explore future research directions in FRP applications. It is particularly suited for researchers, graduate students, structural engineers, and industry professionals engaged in the design, testing, or implementation of FRP technologies.

By showcasing the breadth of research inspired by Dr. Rizkalla’s contributions, this session will serve not only as a tribute to his legacy but also as a platform for shaping the next generation of innovations in FRP systems for civil infrastructure.

Organizers: Amirhossein Mohammadi (University of Minho), José Sena-Cruz (University of Minho), Marta Baena (University of Girona)

Fiber-reinforced polymer (FRP) bars are increasingly adopted in reinforced concrete (RC) structures due to their exceptional corrosion resistance, effectively addressing the high maintenance costs and long-term durability concerns associated with steel reinforcement in aggressive environments such as marine or de-icing salt exposure. However, the distinct mechanical behavior of FRP bars—particularly their linear-elastic response until failure and lack of yielding—necessitates the development of specialized design models that reflect these differences. Although several models have been proposed to predict the structural performance of FRP-reinforced concrete members, their accuracy remains limited.

Recent advances in machine learning, combined with the growing availability of experimental datasets, provide a promising pathway for the development of data-driven AI models capable of predicting the structural behavior of FRP-RC members with significantly improved accuracy. Nevertheless, the model uncertainties, though often smaller than in conventional models—remain non-negligible. Furthermore, the brittle nature and limited ductility of FRP-RC members elevate concerns regarding structural safety and performance under extreme or unexpected loading, underscoring the critical role of structural reliability analysis (SRA) in their design and assessment.

This special session aims to bring together cutting-edge research and practical advancements in the integration of artificial intelligence and structural reliability assessment methods for FRP-reinforced concrete members. It will provide a platform for researchers and practitioners to share innovations in predictive modeling, uncertainty quantification, sensitivity analysis, and reliability-based design approaches, with the ultimate goal of enhancing the safety, efficiency, and resilience of FRP-RC structures.

Organizers: Daniel C. T. Cardoso (Pontifical Catholic University of Rio de Janeiro), Aamir Dean (Leibniz University Hannover), Anilkumar P. M. Nair  (Leibniz University Hannover)

As the demand for sustainable, durable, and high-performance infrastructure grows, Fiber-Reinforced Polymer (FRP) composites have emerged as a transformative solution for reinforced concrete structures. The use of FRP as internal reinforcement (e.g., GFRP bars and grids) and as externally bonded strengthening systems (e.g., laminates and wraps) offers clear advantages, including corrosion resistance, high strength-to-weight ratio and long-term durability. This special session focuses on recent advances in FRP-reinforced and FRP-strengthened concrete structures designed to perform in extreme conditions such as marine and offshore environments, high-temperature exposure, seismic regions and areas subject to impact and fatigue. It aims to bring together researchers, practitioners and industry stakeholders to exchange knowledge, discuss current challenges and identify future directions in the modeling, testing and design of FRP-concrete structures under severe loading and environmental scenarios.

Key Topics (not limited to):

• Development and application of computational models for FRP-concrete members in demanding environments (e.g., offshore platforms, coastal infrastructure, and energy systems).
• Multi-scale modeling strategies for predicting the mechanical behavior and failure of FRP/concrete systems under extreme loading scenarios.
• Experimental investigations and model validation for FRP-concrete structures subjected to fatigue, impact and degradation in aggressive media.
• Advanced testing techniques and long-term performance assessment of FRP-concrete systems under service and extreme conditions.
• Integration of Structural Health Monitoring (SHM) and data-driven maintenance strategies for FRP-concrete structures in corrosive and high-stress environments.
• Innovations in hybrid reinforcement strategies combining FRP with other materials to enhance resilience, structural efficiency and service life in extreme scenarios.

Organizers: Jovan Tatar (University of Delaware), Francesca Roscini (Cusano University)

As the construction industry confronts the urgent challenge of reducing greenhouse gas emissions, fiber-reinforced polymers (FRP) and fabric-reinforced cementitious matrix (FRCM) systems are gaining traction as transformative solutions in structural design and retrofitting. This session, organized on behalf of the IIFC Task Group 1 (Sustainable Fibre Composite Materials), will explore how these materials - particularly those incorporating fibers from natural sources (e.g., basalt, flax, hemp, bamboo, etc.) and/or eco-friendly resins - can be deployed to reduce the embodied and operational carbon footprint of concrete and masonry structures.

We invite contributions that highlight the application of FRP and FRCM systems to support low-carbon strategies, including but not limited to: the use of natural fibers and/or recycled fibers in FRP and FRCM systems; durability assessments under aggressive environmental exposures; innovative structural design solutions that improve performance, reduce maintenance needs, and extend service life; and numerical and design-oriented modelling studies. Submissions addressing novel, multifunctional FRP/FRCM systems - such as self-healing, additively manufactured, or carbon-sequestering variants - are also encouraged.

In addition to technical advances, the session welcomes research on the policy and economic mechanisms that enable broader adoption of low-carbon FRP/FRCM solutions.

Topics may include rating systems, procurement strategies, incentives, and recent developments in codes and standards. Life cycle assessment (LCA) studies focused on in-service phases of FRP/FRCM-reinforced structures are of particular interest.

This session will not consider end-of-life issues such as disposal, recycling or design for reuse. The focus is strictly on upstream and in-service innovations that contribute directly to emissions reduction, durability, and performance optimization in concrete and masonry structures. Interdisciplinary submissions are particularly encouraged.

Organizers: Marco Di Ludovico (University of Naples Federico II), Francesca Ceroni (Università degli Studi di Napoli Parthenope), Annalisa Franco (ITC-CNR)

The use of Fiber Reinforced Polymer (FRP) bars in reinforced concrete structures is increasing day by day thanks to their high durability compared to steel, especially in aggressive environments, and other advantages like lightweight, high tensile strength and magnetic transparency. To ensure successful use of FRP rebars in construction projects, a standardized certification process is essential. Technical specifications have been defined worldwide to determine the essential characteristics and test methods for the qualification of FRP bars and their certification (European Technical Assessment ETA in Europe, ICC-ES Evaluation Report in the United States, and CVT in Italy). Since the properties of FRP bars depend on several factors, a correct characterization is essential to support their broader adoption and integration in the construction industry, promoting innovation and enhancing structural performance.

This Special Session aims to create an open forum to discuss recent results provided by experimental tests on FRP rebars. The collection of data from experimental tests carried out to determine the mechanical, physical and bond properties of several types of FRP bars made by different fibres and with different surface treatments is necessary to promote the evolution and/or revision of codes and guidelines containing specific design provisions for FRP reinforced concrete members.

The Session also covers aspects related to tests specifically developed to determine properties related to working life and durability of FRP bars. The Special Session encourages the comparison of experimental results related to different FRP rebars and the critical analysis of such results also with respect to available literature ones.

Organizers: Juan Murcia-Delso (Universitat Politècnica de Catalunya), Sergio Breña (University of Massachusetts Amherst), Georgia Thermou (University of Nottingham)

Structural retrofit is essential for reducing the damage and collapse vulnerability of existing buildings and infrastructures in regions of moderate to high seismic hazard. Externally bonded fiber-reinforced polymer (FRP) composites have been increasingly adopted for retrofitting reinforced concrete (RC) structures, and significant research has been conducted in the last decades to characterize their effectiveness in improving strength and ductility of RC members. Nowadays, the use of FRP jackets to enhance the shear strength and/or confinement of beams and columns is common, but there is a growing interest in exploring other retrofit solutions using this type of materials.

This special session aims to present and discuss new trends and advances on seismic retrofit of RC structures employing FRP solutions. The topics of interest include, but are not limited to: retrofit of walls or diaphragms, novel FRP systems and hybrid techniques, performance-based analysis and design approaches, and recent updates in design standards and guidelines.

The session targets academics, researchers, practicing structural engineers, and industry professionals involved in FRP design and manufacturing. It is intended to provide a platform to exchange cutting-edge knowledge, demonstrate state-of-the art technologies, identify challenges, foster international collaboration, and highlight emerging trends that can contribute to shape the future of FRP-based seismic retrofit solutions.

Organizers: Niki Trochoutsou (Politecnico di Milano), Liberato Ferrara (Politecnico di Milano)

Integration of novel, smart technologies within new construction or existing infrastructure can enhance durability and ensure timely intervention before safety is jeopardised. To this end, imparting engineered self-sensing and self-monitoring functionalities in advanced composites without compromising their structural performance can guarantee a step-change in structural health monitoring and pro-active maintenance strategies and foster a resilient, sustainable future.

In this special session, we invite research contributions on the development of intelligent, all-in-one structural and sensing systems for smart construction and structural strengthening comprising non-metallic internal or externally bonded reinforcement. Key advancements in the design, material composition and integration of smart FRP bars, externally-bonded FRPs, NSM reinforcements, and TRM composites are particularly encouraged. In this context, we particularly welcome contributions on functionalisation approaches, including but not limited to:

• Incorporation of electrically conductive nano- or micro-inclusions within the matrix,
• Integration of piezoelectric or piezoresistive transducers,
• Distribution and embedding of fibre optic sensors,
• Use of smart coatings or “intelligent skins”.

Effectiveness in terms of sensor-material compatibility, strain, crack and damage sensing, as well as damage localisation should be highlighted with a view of discussing both scientific and technological challenges in detecting early-stage complex failure mechanisms and interpreting sensor data. Additional emphasis will be placed on durability and long-term reliability of smart monitoring systems in various environmental conditions and real-world implementation of smart composite structural systems. Image-based modalities to corroborate ‘’intelligent’’ characteristics, such as Digital Image Correlation or Electrical Resistance Tomography are of high interest.

This session aims to foster cross-disciplinary collaboration between researchers, industry professionals, and practitioners from materials science, structural engineering, and sensor technology, and to define a forward-looking roadmap towards resilient and adaptive smart infrastructure.

Organizers: Giuseppina Amato (Queen's University Belfast), Su Taylor (Queen's University Belfast)

This special session aims to explore the dynamic performance of Textile-Reinforced Mortar (TRM) systems when subjected to medium and high strain rates, with a focus on applications in the strengthening and retrofitting of concrete structures exposed to dynamic and impact loading.

While TRM systems have gained significant attention as a sustainable and fire-resistant alternative to Fiber-Reinforced Polymers (FRPs), its behavior under dynamic loading conditions remains an emerging area of research with critical implications infrastructure resilience.

The session seeks to bring together researchers to discuss recent advances in experimental testing, numerical modelling, and analytical methods for understanding TRM performance under various dynamic loading scenarios. Specific topics will include: strain rate sensitivity of TRM constituents (mortar matrices and textile reinforcements), test methods for dynamic characterization, tensile and interfacial bond behavior at high loading rates, and case studies of TRM-strengthened structures under impact events.

This session is targeted at academics, structural engineers, material scientists, and stakeholders in infrastructure resilience and retrofitting. It will contribute to the development of robust design guidelines and performance-based assessment methods for TRM systems in dynamic applications.

Expected outcomes include identification of research gaps, promotion of collaborative projects, and dissemination of findings to inform future code development.

Organizers: Baolin Wan (Marquette University), Guan Lin (Southern University of Science and Technology), Lucija Stepinac (University of Zagreb)

While traditional manufacturing techniques have greatly facilitated the use of FRP in civil infrastructure, recent developments in advanced manufacturing technologies have paved the way for new possibilities. Emerging processes such as 3D printing and automated manufacturing offer great potential for improving the precision, cost reduction, customization, and sustainability of the applications of FRP in civil infrastructures. Given the rapid developments in this field, it is important to provide a dedicated session in FRPRCS17 to discuss the latest innovations, challenges and applications of advanced FRP manufacturing technologies in construction. This special session will bring together researchers, practitioners and industry at the forefront of this exciting field to provide opportunities for academic exchange and collaboration.

The proposed session will cover a wide range of topics related to advanced FRP manufacturing techniques, including but not limited to:

• 3D printing of FRP composites: materials, processes, and applications
• Additive manufacturing of FRP for structural applications
• Sustainability and efficiency in advanced FRP manufacturing
• Case studies and practical implementations of 3D printed FRP in construction

This session will complement the overall conference theme by providing insights into the next generation of FRP manufacturing processes. As the construction industry increasingly seeks ways to incorporate advanced technologies, a special session on this topic will enhance the technical diversity of the conference and engage both academic and industry professionals.

Organizers: Georgia Thermou (University of Nottingham), Marta Del Zoppo (University of Naples Federico II), Marco Di Ludovico (University of Naples Federico II)

Many existing reinforced concrete (RC) buildings and infrastructure elements do not meet current code requirements, are affected by evident degradation and exhibit inadequate performance during extreme events. In response, fibre-reinforced composites have emerged as promising solutions for enhancing flexural and shear capacity while improving overall ductility and durability. Recent advancements in this field include integrating sustainable materials, developing multifunctional composites, and using digital design and monitoring tools to optimise strengthening interventions.

This Special Session invites contributions presenting experimental, analytical, and numerical studies on the use of Fibre-Reinforced Cementitious (FRC) composites for retrofitting existing substandard constructions. The focus is on Engineered Cementitious Composites (ECC), Strain Hardening Cementitious Composites (SHCC), Ultra-High Performance Fibre Reinforced Cementitious Composites (UHPFRCCs), hybrid systems, and other innovative systems that fall within the same category and are multifunctional. Contributions are welcome at all scales—from material characterisation to component-level and full-structure applications, targeting RC structures (e.g. buildings, bridges, tunnels, nuclear plants).

This session aims to be a dynamic platform for knowledge exchange among researchers, practitioners, and industry experts, fostering innovation and collaboration in the vital field of structural retrofitting.

Organizers: Eric Jacques (Virginia Polytechnic Institute and State University), Aniket Borwankar (Simpson Strong-Tie), Enrique del Rey Castillo (University of Auckland)

This special session brings together international experts advancing the use of FRP materials to retrofit deficient reinforced and precast concrete diaphragms – a critical, yet often overlooked, component in structural retrofitting. Diaphragms play a central role in transferring lateral loads to vertical lateral force resisting elements, but many existing buildings – particularly older, nonductile structures in seismic regions – lack sufficient in-plane capacity. Despite this, current design codes such as ACI 318, ASCE 41, and ACI 440 provide limited guidance on evaluating or strengthening diaphragms.

The session highlights recent advances in experimental testing, analytical modeling, and design integration focused on strengthening diaphragms with externally bonded FRP. Topics include large-scale reverse cyclic testing of FRP-strengthened collectors and panels, force transfer mechanisms at diaphragm-wall interfaces, anchorage strategies, and system-level behavior of multi-bay specimens with slab openings. Presentations will also showcase modeling approaches to evaluate internal force flow and identify discrepancies between traditional flexural models and observed response. These insights aim to refine design assumptions and improve retrofit strategies.

This session is intended for structural engineers, researchers, and material specialists seeking actionable, validated solutions for diaphragm retrofitting. Attendees will gain a deeper understanding of detailing techniques, FRP performance limits, and how analytical tools can inform retrofit decisions for floor diaphragms. By bridging the gap between research and practice, the session supports ongoing efforts to develop consensus-based design guidance and drive the adoption of FRP retrofits for diaphragm applications in concrete buildings.

Organizers: Roberto A. Lopez-Anido (University of Maine), Brahim Benmokrane (University of Sherbrooke)

Commercially available thermoset composite rebar is manufactured by the pultrusion process and has surface profiles or deformations made with secondary manufacturing processes. A significant shortcoming of thermoset rebar is that it cannot be field bent after initial fabrication, and common configurations such as hooked bars, stirrups and spirals must be created during the primary manufacturing process. This limits adaptability during construction and increases cost.

A promising solution to ensure both corrosion resistance and field bendability is to fabricate composite rebar using thermoplastic polymers. Since thermoplastic polymers do not cross-link, they can be reshaped after forming with heat
enabling field bending of composite rebar. However, the high processing viscosities of thermoplastics hinder fiber saturation, which makes conventional pultrusion of thermoplastic composite rebar challenging.

The specific topics to be covered in the session are focused on thermoplastic composite rebar and include advances in manufacturing, characterization of thermoplastic polymers, thermo-mechanical properties, assessment of environmental durability, high-temperature performance, fire resistance, concrete reinforcement, field bendability, performance-based qualification criteria, design specifications and recycling.

The target audience are reinforced concrete designers, code approval entities, manufacturers and composite researchers. The expected outcomes or impact of the session are to become familiar with the state-of-the-art on thermoplastic composite rebars for concrete reinforcement, gain an understanding on advantages and challenges of this technology and generate a discussion on opportunities for implementation and commercialization.

Organizers: Chao Wu (Imperial College London), Amr El-Nemr (The German University in Cairo), Ali Hadigheh (University of Sydney)

Fibre reinforced polymers (FRP) have demonstrated great potential as structural materials due to their outstanding mechanical and durability properties. As the use of FRP expands across various industries, including aeronautics, aerospace, wind energy, and construction, it becomes crucial to address their end-of-life management to reduce environmental impact and maximize their lifecycle potential. Several sectors, such as the wind and aeronautic industries, are already encountering challenges with the disposal of structural composite components that retain excellent mechanical properties and can be repurposed in other industries, such as civil engineering.

This Special Session aims to explore innovative approaches for the sustainable management of FRP composites at the end of their lifecycle. Topics will include but not limited to: i) recycling strategies, ii) repurposing opportunities, iii) regulatory frameworks, and iv) emerging technologies that can support the circular economy in industries relying on these advanced materials. Furthermore, life cycle analysis (energy inputs, CO2 emissions and other environmental aspects) is also an important topic of the session as it shall shed light on the truth sustainability potential of the approaches presented.

Organizers: Maurizio Guadagnini (The University of Sheffield), Maria Lopez de Murphy (Modjeski and Masters, Inc.)

Meeting pressing sustainability goals requires more durable structural solutions, making the wider adoption of innovative reinforcing materials for concrete structures increasingly crucial. Significant advancements have been made in the field of Fiber Reinforced Polymer (FRP) reinforcement and important milestones have been achieved in the past few years, including the publication of new guidelines, standards and certification documents.

This session will o􀆯er a critical overview of design recommendations, standards and certification pathways from various regions worldwide, highlighting their fundamental principles, design philosophies, and practical applications.

By bringing together leading researchers, infrastructure owners, material manufacturers, designers and members of standards and code committees, this session will foster an open dialogue on best practices, current limitations, and future directions.

The discussions will aim to foster the development of a harmonised framework for the specification and design of FRP reinforcement for concrete structures, ultimately enhancing confidence and facilitating its wider adoption.

Organizers: Veronica Bertolli (Politecnico di Milano), Carlos Ribas González (University of the Balearic Islands), Lesley H. Sneed (University of Illinois Chicago)

Externally bonded (EB) and near surface mounted (NSM) reinforcements have been effectively adopted as shear strengthening of existing concrete members. Among the available reinforcements, both organic- and inorganic-matrix composites have been attracting great attention due to their interesting features, such as high strength-to-weight ratio and durability. In addition, composite bars have been used as internal reinforcement of new concrete structures in applications where their physical and mechanical properties make them a valuable alternative to traditional steel reinforcing bars. Investigating the shear capacity of these concrete members is a complex task that requires a deep understanding of the different contributions to the beam shear capacity - namely, concrete, internal transverse shear reinforcement (steel or composite) and externally applied reinforcement (if any) contributions.

This Symposium aims at collecting recent advancements in the study of the shear behavior of concrete members reinforced with organic- and inorganic-matrix composites. Topics of particular interest for this Symposium are, although not limited to: 1) use of FRP and FRCM/TRC/TRM as externally applied (EB and/or NSM) shear reinforcement of RC members; 2) shear capacity of FRP-reinforced concrete members with and without internal transverse shear reinforcement; 3) analytical modelling and guidelines provisions for estimating the shear capacity of composite reinforced concrete members; 4) advanced numerical modelling of shear resisting mechanisms.

The Symposium is intended to bring together experts at the forefront of research on the shear behavior of concrete members reinforced with innovative composite materials, providing the opportunity for the advancement of the state of knowledge on this topic.