Alexander Salenikovich et Kiavash Gholamizoj ont participé à la prestigieuse World Conference on Timber Engineering (WCTE 2025), qui s’est tenue du 22 au 26 juin à Brisbane, en Australie. Réunissant 940 participants de 44 pays, dont 68 du Canada, cet événement d’envergure internationale constitue le principal forum scientifique pour la présentation et la discussion des avancées en recherche, en enseignement et en pratique dans le domaine du génie et de la construction en bois. Depuis 1984, le WCTE se tient tous les deux ans dans différentes régions du monde. Alexander Salenikovich a d’ailleurs joué un rôle clé en tant que responsable du programme scientifique lors de l’édition 2014 à Québec. Le prochain congrès aura lieu à Edmonton, en Alberta, en août 2027.
Lors de cet événement, Alexander Salenikovich a joué un rôle de premier plan en tant que membre du comité scientifique, contribuant activement à la qualité et au bon déroulement du congrès. Sur place, il s’est également démarqué par une participation soutenue : il a présidé quatre sessions, présenté deux communications issues de ses travaux de recherche et co-signé quatre autres présentations. Par l’ampleur et la diversité de ses interventions, il a pleinement contribué à la diffusion des connaissances et au rayonnement du génie du bois sur la scène internationale. Une implication remarquable qui témoigne de son leadership scientifique et de son engagement envers la communauté. Sa première communication, intitulée « Development of Safe Design Procedures for Products, Assemblies, and Systems in Wood Construction », expose un programme de recherche quinquennal financé par le Québec, visant à développer des procédures de conception sécuritaires pour les produits et systèmes en construction bois. Ce projet inclut notamment la mise au point de nouvelles solutions pour les connexions, les cadres bois-acier ainsi que des directives parasismiques innovantes. La seconde communication, « Brittle Failure of CLT Connections with Inclined Self-Tapping Screws », aborde les modes de rupture fragile des connexions en bois lamellé croisé (CLT) utilisant des vis autotaraudeuses inclinées. Cette étude révèle des mécanismes complexes de défaillance et propose des recommandations pour améliorer les normes canadiennes de conception, renforçant ainsi la sécurité et la performance des constructions en bois massif. Ces travaux, à la fois novateurs et rigoureux, illustrent parfaitement la contribution d’Alexander Salenikovich au rayonnement scientifique et à l’innovation dans le domaine du génie du bois.
Par ailleur, Kiavash Gholamizoj a présenté ses travaux de recherche intitulés «Experimental tests on connections with dowels and slotted-in steel plates under cyclic loading» au cours de la session Engineering (5D) le 24 juin 2025. Sa présentation, chaleureusement accueillie, a suscité un vif intérêt et donné lieu à des échanges enrichissants avec les participants. Son projet vise à optimiser les assemblages ductiles dans les cadres de contreventement en bois massif, essentiels à la dissipation d’énergie lors de séismes. Il mène des essais expérimentaux afin d’évaluer leur rigidité, résistance, ductilité et modes de rupture, en tenant compte notamment de l’espacement des goujons et des distances aux extrémités. En marge de sa présentation, Kiavash a assisté à plusieurs sessions portant sur la conception sismique, les systèmes hybrides, les assemblages innovants, ainsi que le développement des normes et la durabilité des constructions en bois. Ces échanges lui ont permis de découvrir de nouvelles approches expérimentales et de modélisation, d’approfondir sa connaissance des codes internationaux, et de renforcer ses liens avec des chercheurs d’universités de renom telles que McGill, Waterloo et l’Université de l’Alberta. Fort de ces retours et collaborations, Kiavash prévoit d’intégrer les commentaires reçus dans sa thèse doctorale en cours, de poursuivre le dialogue avec des chercheurs d’universités renommées telles que l’Université de l’Alberta, McGill et Waterloo, et d’enrichir ses publications scientifiques avec les dernières avancées présentées lors de la conférence. Kiavash tient à exprimer sa profonde gratitude envers son directeur de recherche, le professeur Alexander Salenikovich, ainsi que les partenaires financiers et administratifs qui ont rendu cette participation possible : la subvention Alliance du CRSNG Next-Generation Wood Construction, le Ministère des Ressources naturelles et des Forêts du Québec (MRNF) et le Centre de recherche sur les matériaux renouvelables (CRMR), via son programme de mobilité (1000$). Cette expérience marque une étape significative dans l’avancement de ses recherches et de son développement professionnel.
Félicitations à Kiavash et Alexander pour leur brillante participation et leurs contributions remarquables dans le domaine du génie du bois !
Pour en savoir plus sur la WCTE 2025, consultez cette vidéo!
EXPERIMENTAL TESTS ON CONNECTIONS WITH DOWELS AND SLOTTED-IN STEEL PLATES UNDER CYCLIC LOADING – Presented by Kiavash Gholamizoj
Kiavash Gholamizoj, Alexander Salenikovich, Ying Hei Chui , David Hanna
Modern mass timber braced frames rely on ductile connections to dissipate energy effectively. However, brittle failure modes in dowel-type connections may occur before the fasteners yield, limiting ductility and energy dissipation capacity. This study addresses these challenges by conducting experimental cyclic tests on dowel connections with slotted-in steel plates. Connections were designed per CSA O86Â and tested to evaluate stiffness, resistance, ductility, energy dissipation, and failure modes, as well as to compare the two design approaches. The tested connections form part of glulam brace elements in multi-storey timber braced frames. Each joint includes 12.7 mm (1/2-in.) dowels in various configurations at one end, while the opposite end, features steel side plates with inclined self-tapping screws, overdesigned to allow for reuse across tests. A total of 32 tests were conducted across four series using 12 dowels in various spacings. Each series included two static tests and six one-directional cyclic tests in axial tension. The static tests are used to determine the cyclic displacement protocols based on ISO 16670. Performance parameters, derived from load-slip graphs, highlight the effects of fastener spacing and end distance on resistance and failure modes. Experimental results are compared with predictions from CSA O86, providing insights for designing reliable connections that meet the high force demands of mass timber braced frames.
DEVELOPMENT OF SAFE DESIGN PROCEDURES FOR PRODUCTS, ASSEMBLIES, AND SYSTEMS IN WOOD CONSTRUCTION- Presented by Alexander Salenikovich and Matiyas Bezabeh
A. Salenikovich , M.A. Bezabeh , C.A. Rogers , C. Dagenais
The Canadian government and its provinces are implementing climate strategies and regulations to decarbonize the building construction sector through nature-based solutions, such as using sustainable and renewable construction materials. Measures include promoting wood education and research, “Wood First » provincial policies, modernizing sustainable forest management, and strengthening the timber supply chain. In line with these efforts, in 2023, the Québec Ministry of Natural Resources and Forests funded the authors of this paper to develop safe design procedures for products and systems in wood construction. The research program will be executed over five years at Université Laval and McGill University in collaboration with twelve industry partners through a series of planned research tasks. The tasks encompass developing 1) novel connection systems for mass timber buildings, 2) new timber-steel braced frames, 3) low-damage rocking timber frame braced systems, and 4) seismic and wind design guidelines for the new systems through numerous experimental campaigns and extensive numerical studies. This paper provides an overview of the project, its status, and upcoming tasks.
BRITTLE FAILURE OF CLT CONNECTIONS WITH INCLINED SELF-TAPPING SCREWS- Presented by Alexander Salenikovich
Amir Einipour, Alexander Salenikovich, Jianhui Zhou, Thomas Tannert
Cross-laminated timber (CLT) is increasingly being used in construction, but its brittle nature when loaded in tension or shear parallel to grain poses design challenges since the crosswise layup makes CLT behave differently from solid timber or glulam. Self-tapping screws (STS) are versatile fasteners in timber construction, acting in shear when installed perpendicular to the connection interface or in withdrawal when inclined. The 2024 edition of the Canadian Standard for Engineering Design in Wood (CSA O86) includes design provisions for STS, but guidance on estimating brittle failures of STS connections in CLT remains limited. In this paper, experimental investigations assessing the performance of CLT connections with inclined STS and steel side plates using multiple configurations, considering CLT layup, screw penetration length, and screw edge distance, are presented. The observed brittle failure modes across different test series were more complex than those outlined in CSA O86, including occurrences of rolling shear and layer separation alongside the predominant plug shear. Using screws of the same length in CLT with different layups affected the load-carrying capacity due to changes in the failure plane. Connections near the panel edge showed lower capacity than those in the centre, highlighting the impact of edge distance on brittle failure. Based on these findings, changes to the CSA O86 design provisions will be proposed.
BRITTLE FAILURE MODES IN CONNECTIONS WITH SELF-TAPPING SCREWS IN GLULAM AND CLT- Presented by Ying Hei Chui
Jan Niederwestberg, Chun Ni, Ying Hei Chui, Alexander Salenikovich
Self-tapping screws (STS) have become the fastener of choice for mass timber construction. They are used either as laterally or axially loaded fasteners. In lateral loading, STS connections are generally designed using the European Yield Model, which considers embedment and fastener yielding. Brittle failure modes, influenced by geometric factors such as end and edge distances and fastener spacing, are checked separately. As part of developing STS design provisions for the Canadian timber design standard, thirty STS connection configurations in glulam timber and cross-laminated timber (CLT) were tested in order to determine their behaviour and failure modes. The results show that STS connections generally tend towards yield failures when recommended fastener arrangements are used. However, connections in CLT are prone to brittle failure modes if fastener spacings arrangements are unfavourable.
STIFFNESS OF TIMBER CONNECTIONS WITH DOWEL-TYPE FASTENERS UNDER LATERAL LOAD- Presented by Ying Hei Chui
Tao Gui, Ying Hei Chui, Alexander Salenikovich
When designing structural timber systems, serviceability limit states (SLS) can govern the final design solutions. Deformations in mechanical timber connections play a key role in controlling common SLS, such as vibration and deflection, which are dependent on the stiffness of the connections. It is also required for ultimate limit states (ULS) design. For instance, in statically indeterminate structures where the applied design load is resisted simultaneously by more than one component, and the load distribution is governed by stiffness properties of these components. Therefore, accurate models predicting the deformation or stiffness of timber connections are required for design purposes. Early timber connection models were largely based on the theory of beam on elastic foundation (Winkler foundation). Winkler foundation model works reasonably well for strength prediction but not stiffness. This is because the Winkler theory tends to lead to an over-estimation of the deformation due to the assumption of decoupling of the foundation springs. An improved approach is necessary for connection stiffness prediction. This paper investigates the use of Multi-spring foundation and Half-space foundation theories to address the limitations of Winkler foundation model. Finite element models based on the three different foundation theories were developed and the predicted results are compared. Â It was found that the Multi-spring foundation and Half-space foundation theories provide more accurate predictions of connection stiffness for dowel-type fasteners compared to the Winkler foundation theory. However, further experimental studies are required to determine the specific application ranges of these models.
DEVELOPMENT AND SEISMIC DESIGN OF NOVEL HYBRID TIMBER-STEEL ECCENTRICALLY BRACED FRAMES –Presented by Matiyas Bezabeh
Abebaw A. Mekonnen, Mairvat Abdulhamid1, Matiyas A. Bezabeh1, Colin A. Rogers1, Alexander Salenikovich
Described in this paper is the development of a novel hybrid timber-steel eccentrically braced frame (TS-EBF), that has significant benefits in terms of seismic performance and sustainability. This new seismic-force-resisting system (SFRS) aims to combine the sustainability and lateral stiffness of timber-braced frames with the excellent energy dissipation capacity of steel links for enhanced seismic performance. The system uses structural steel for deformation-controlled elements (ductile shear links) and engineered wood products for force-controlled elements (beams, columns, and diagonal braces). A six-storey archetype building that uses this novel SFRS was designed using both force- and displacement-based seismic design approaches for the seismicity of Victoria, British Columbia, Canada. Numerical models were developed for ductile shear links in ABAQUS finite element software and validated with full-scale quasi-static cyclic tests. In addition, a two-dimensional fiber-based numerical model of the prototype six-storey building was developed in OpenSeesPy. Performance assessment was carried out using static pushover and nonlinear response history analyses using thirty-three hazard-consistent ground motion records. Overall, this study demonstrated the effectiveness of this new lateral system, indicating its potential as an alternative SFRS in Canada’s high-seismic risk regions.