ERIES - ALL4wALL 2023 Blind Prediction Competition: Shake-table Response of 40-ton RC U-shaped Wall


Final Report

The "All4wALL 2023 Blind Prediction Competition" has concluded.

You can find an overview of the predictions and the winners in the report available in the Given Information section

Invitation and Overview: July 2023

The Civil and Environmental Engineering (GCE) group in the Institute of Mechanics, Materials, and Civil Engineering (iMMC) at UCLouvain, together with the support of the National Laboratory for Civil Engineering (LNEC), Portugal, invites you to participate in the prediction of the dynamic shake-table response of a 40-ton reinforced concrete (RC) U-shaped wall. The unit will be tested in late 2023 in the shake table of LNEC. The deadline for the submission of the blind predictions is Friday March 15, 2024 at 11:59 PM (CEST).

Continue reading for some general information. Refer to the side menu for complete instructions on how to participate. From the side menu, you can also register your email address, which will allow you to be the first to receive the “News & Updates” that will also be posted on the corresponding section of this webpage.

This experimental program is primarily funded by ERIES (Engineering Research Infrastructures for European Synergies) Transnational Access program. The project is called “ALL4wALL – Smart ALLoys for WALLs: towards durable structures with long service lives and minimal seismic residual displacements”. The user group of the ERIES – ALL4wALL is composed of seven institutions: Université catholique de Louvain (UCLouvain), ENPC ParisTech, ISAE-Supméca - Institut supérieur de mécanique de Paris, University of Liège, University of Ljubljana, University of Pavia, and York University (Canada).

This competition is designed to cater to a wide range of participants, from those with limited available time that wish to use simplified models (namely pushover analyses), to those willing to employ more refined simulation tools for the simulation of the nonlinear dynamic response. To this end, participants are allowed to submit just a compulsory set of basic data or a full set of information including more refined optional data. Participants can consist of individuals or teams. Three categories are considered: practicing engineers, researchers, and students (up to and including doctoral level).

An open online live video session, towards the end of April 2024, will release the main (anonymised) results and announce the winners. This information will also be posted on this website. Some of the winners of each category will be invited to briefly present their method of prediction during the live session, and later in a technical session at the WCEE2024, “CMS-1: RC structural walls: advances and future challenges for design, modelling, testing, and construction”, which currently counts with 62 submitted abstracts. They will be able to present in person if they are attending the conference, or online if they are not.

Finally, please share this invitation with your colleagues and encourage them to participate. We are looking forward to receiving your predictions!

Submission of Predictions

To submit one or several predictions, the available response form must be completed and uploaded until the deadline, Friday March 15, 2024 at 11:59 PM (CEST).

The prediction submission sheet was designed to minimise the expected time required to participate. Two types of information sets can be provided by the participants. The first type is compulsory basic information (e.g., failure mode, maximum relative displacement, maximum lateral inertial force, etc.), whereas the second type is optional information including quantities that may require more computation time and effort (e.g., maximum tensile strain, residual displacements, energy dissipation, plastic hinge length, etc.).

All simulation approaches are allowed, including hand calculations from methods defined in building codes, guidelines, published research, as well as numerical modelling.

Motivation and Objective

U-shaped RC walls are the most popular geometry among the possible shapes of core walls forming the backbone of millions of buildings internationally. They are well suited to accommodate elevator shafts or staircases and represent the structural lateral-load bracing system, namely against wind and seismic loads. As the global number of buildings are expected to double until 2060, core walls will play a critical role in the resilience of the built environment.

RC core walls are unavoidably subjected to bidirectional and torsional demands (i.e., twisting) during the seismic response of the building. The additional stresses induced in the wall from warping could result in a premature failure when combined with the stresses already generated from the flexural response of the structure. Another interconnected topic lacking remarkably in terms of experimental investigation are residual displacements, which are key in determining the post‐earthquake repairability of wall structures. The current shake table tests will allow to study the two above aspects, as well as the interaction of torsion and flexure in the dynamic response of RC U‐shaped core walls, and hence contribute to a better understanding of their target performance.

The ERIES - ALL4wALL 2023 blind prediction competition will also allow assessing the state of practice in evaluating RC walls subjected to flexure and torsion, to observe the range of approaches that engineers use, and to analyse the results that these approaches provide. This prediction competition will gain insight into the methods for assessing the behaviour, strength, and deformation capacity of RC U-shaped walls.

It is hoped that the results of this contest will promote good seismic design practices for RC walls, in particular including torsional actions within design and assessment. The shake table tests and the predictions can help improving the assessment of RC wall buildings and provide directions for future building code revisions. More broadly, this competition contributes to promote a more robust building stock and helps to strengthen community resilience internationally.

Organisation and Acknowledgements

The ERIES - ALL4wALL 2023 blind prediction main organisers are Dr. Ryan Hoult and Prof. João Pacheco de Almeida (UCLouvain), together with the support of Dr. António Correia (LNEC). However, these complex experimental tests would not happen without the collaboration of many other motivated collaborators. They include:

  • the ERIES – ALL4wALL user group members, namely (in alphabetic order): Mr. Alex Berthloet, Dr. Andrea Orgnoni, Dr. Antonio Janevski, Prof. Aude Simar, Mr. Basile Payen, Prof. Boyan Mihaylov, Prof. Catherine Doneux, Prof. Dan Palermo, Dr. Gwendal Cumunel, Prof. Rui Pinho, Dr. Stefania Lo Feudo, Prof. Tatjana Isakovic, Dr. Yunyeok Han;
  • the scientific and technical staff of LNEC;
  • the support of the Mechanical Testing, Structures, and Civil Engineering Laboratory (LEMSC, UCLouvain), headed by Prof. Catherine Doneux, namely Alex Bertholet, Antoine Bietlot, and Pierre Mertens. Our appreciation also goes to the Institute of Mechanics, Materials, and Civil Engineering (iMMC) at UCLouvain at large, and more specifically to Sophie Labrique for all the help with the communication and the website, as well as Nathalie Sergoigne for the administrative matters.


The U-team

The UCLouvain 2022 Blind Prediction Competition team: Catherine Doneux, Christophe Bayard, Frédéric Gorski, Karen Campana, Antoine Bietlot, Joao Almeida, Sacha Awad , Pierre Mertens de Wilmars, Alex Bertholet, Ryan Hoult