Seismic performance and residual displacements of reinforced concrete walls detailed with iron-based shape memory alloys

Projektinformationen

SMA-RC-Walls

ID Finanzhilfevereinbarung: 101061439

DOI

10.3030/101061439

Projekt abgeschlossen

EK-Unterschriftsdatum 6 Juli 2022

Startdatum 1 Juli 2023

Enddatum 30 Juni 2025

Finanziert unter

• Marie Skłodowska-Curie Actions (MSCA)

Gesamtkosten

Keine Daten

EU-Beitrag

€ 191 760,00

Koordiniert durch

UNIVERSITE CATHOLIQUE DE LOUVAIN
Belgium

Periodic Reporting for period 1 - SMA-RC-Walls (Seismic performance and residual displacements of reinforced concrete walls detailed with iron-based shape memory alloys)

Berichtszeitraum: 2023-07-01 bis 2025-06-30

Zusammenfassung vom Kontext und den Gesamtzielen des Projekts

Reinforced concrete (RC) remains essential to the seismic resilience of mid- and high-rise buildings globally, especially in resisting lateral loads, despite growing interest in alternative sustainable materials. While RC structures are designed to prevent collapse during major earthquakes, events like the 2011 Christchurch earthquake revealed that severe residual displacements can render buildings uneconomic to repair, leading to widespread demolition and societal disruption. This has prompted a shift toward new performance targets focused on minimizing damage and ensuring post-earthquake functionality. To meet these goals, this research proposes the development of RC walls reinforced with iron-based Shape Memory Alloys (SMAs), which offer self-centering capabilities and energy dissipation, potentially reducing residual displacements and economic losses after seismic events.
This study aims to revolutionize reinforced concrete wall systems by integrating iron-based Shape Memory Alloys (SMAs) to enhance seismic resilience and sustainability. Key objectives include designing SMA rebars with optimal pseudoelastic performance, developing a reliable steel-to-SMA connection using inertial friction welding, and improving bond performance with environmentally friendly coatings. The project also involves experimental testing of boundary prisms and full-scale RC walls to assess axial behaviour, lateral capacity, and residual displacement reduction. Finally, a mechanical model will be developed to predict residual displacements, supporting more resilient and cost-effective seismic design practices.

Arbeit, die ab Beginn des Projekts bis zum Ende des durch den Bericht erfassten Berichtszeitraums geleistet wurde, und die wichtigsten bis dahin erzielten Ergebnisse

To gain deeper insight into the seismic performance of RC core walls, dynamic shake table tests were performed on two wall units: UWS1, reinforced with conventional steel, and UWS2, which featured largely-debonded iron-based Shape Memory Alloy (FeSMA) rebars. In UWS2, pre-stressing was applied to the FeSMAs via Joule heating to help reduce residual displacements. Both units were subjected to alternating uni- and bidirectional ground motions, with advanced data acquisition systems capturing key engineering responses throughout the tests.
Another experimental program under the envelope of the SMA-RC-Walls MSCA project focused on testing half-scale reinforced concrete boundary elements representing the critical end regions of a 4 m-long planar wall, scaled to simulate a 10-storey mid-rise structure with a high shear span. The test units—300 mm × 125 mm × 1600 mm prisms—were subjected to quasi-static, reverse-cyclic axial loading to mimic the axial tension-compression demands experienced during seismic events. While the setup applied uniform strain distributions and did not capture the complex strain gradients or out-of-plane restraint provided by the wall web, it allowed cost-effective, conservative testing of key parameters such as residual displacement, energy dissipation, crack behaviour, and instability. Advanced instrumentation, including both conventional and high-resolution tools, was employed to comprehensively assess the structural response of these boundary elements.
The outcomes of these critical experimental tests include: (i) publicly available datasets hosted in an open-access online repository, providing a valuable resource for validating and enhancing computational models of RC wall behaviour; and (ii) two peer-reviewed journal articles currently under review in leading international journals.

Fortschritte, die über den aktuellen Stand der Technik hinausgehen und voraussichtliche potenzielle Auswirkungen (einschließlich der bis dato erzielten sozioökonomischen Auswirkungen und weiter gefassten gesellschaftlichen Auswirkungen des Projekts)

Future research should leverage the open-access experimental data to validate and refine numerical models simulating RC walls reinforced with iron-based shape memory alloys. Continued studies examining the seismic performance of such systems will further support the adoption of this innovative reinforcement for enhancing the resilience of concrete infrastructure.

Boundary Elements of RC Walls Tested Uniaxially

Reinforced Concrete Core Wall on Shake Table Pre-Test