Shear behaviour of RC-UHPFRC composite beams without transverse reinforcement

Shear resistance and structural hardening resistance models for hybrid NSC-UHPC elements

“…In this paper, the failure from concrete crushing at the node-to-strut interface of node N c is assessed since it is the most frequent failure mode observed for elements with good NSC-UHPC interface and with good UHPC placement (Ji and Liu, 2020;Noshiravani and Brühwiler, 2013;Pharand and Charron, 2022a;Sine et al, 2022;Yin et al, 2017).…”

“…Through this concept, many experimental campaigns were realized to study the bending behaviour of hybrid NSC-UHPC elements (Habel, 2004; Makita, 2014; Oesterlee, 2010; Wuest, 2007; Al-Osta et al, 2017; Denarié et al, 2003; Lachance et al, 2016; Noshiravani and Brühwiler, 2013; Paschalis et al, 2018; Prem and Murthy, 2016; Safdar et al, 2016; Zingaila et al, 2017; Pharand, 2022; Yin et al, 2017). However, only a few (Pharand and Charron, 2022a; Sine et al, 2022; Noshiravani and Brühwiler, 2013; Ji and Liu, 2020; Yin et al, 2017) specifically studied the shear behaviour of hybrid NSC-UHPC elements.…”

“…First, shear load is resisted by monolithic action alike NSC element (solid green line in Figure 1(a)). Within this first stage, the ultra-high performance concrete (UHPC) layer, reinforced or not, increases the capacity of the shear transfer mechanism in the NSC and delays the apparition of a diagonal shear crack (Noshiravani and Brühwiler, 2013; Sine et al, 2022; Pharand and Charron, 2022a; Yin et al, 2017). Second, upon the occurrence of a diagonal shear crack, shear load is resisted by a composite mechanical action (bold doted orange line in Figure 1(a)) also named double hinges mechanism by Noshiravani and Brühwiler (2014).…”

“…Second, upon the occurrence of a diagonal shear crack, shear load is resisted by a composite mechanical action (bold doted orange line in Figure 1(a)) also named double hinges mechanism by Noshiravani and Brühwiler (2014). Within this second stage, the UHPC layer, reinforced or not, enables a structural hardening behaviour by forming two plastic hinges and reduces the stress sustained by the NSC (Noshiravani and Brühwiler, 2013; Pharand and Charron, 2022a; Sine et al, 2022; Bastien-Masse and Brühwiler, 2016). Capacity gained from this second stage is such that shear failure could even be avoided on shear deficient NSC elements (Pharand, 2022; Yin et al, 2017).…”

“…The main failure criteria observed for the composite mechanical action is concrete crushing of subsection S2 at the tip of the diagonal shear crack (Ji and Liu, 2020; Noshiravani and Brühwiler, 2013; Pharand and Charron, 2022a; Sine et al, 2022; Yin et al, 2017) (Figure 1(b)). Nonetheless, complete UHPC delamination beyond the loading plate (Figure 1(b)) and UHPC tensile failure prior to concrete crushing were also observed (Pharand and Charron, 2022a; Houdoin, 2022).…”