Analytical assessment for adhesively bonded timber-concrete composite ceilings based on experimental evaluation

Adhesively bonded timber-concrete composite (TCC) systems enable continuous composite action and dry prefabrication, yet full-scale behaviour and the adequacy of Eurocode γ -method design remain uncertain. Bonded TCC ceiling elements produced with two strategies (pocket and channel methods) were tested in static four-point bending. Load–deflection response, bending stiffness, interface slip and failure modes were measured and compared with γ -method models extended by a Timoshenko shear term. Specimens were stiff and quasi-linear over a large load range, then showed gradual stiffness loss governed by nonlinear concrete compression. Transverse shear contributed up to 8 % of total deflection for stocky ribs but <4% for slender ribs. Global stiffness was governed mainly by timber and, secondarily, concrete elastic moduli. Beyond system-specific thresholds, the adhesive elastic-modulus and interface-stiffness had only minor influences on the global structural response. Both manufacturing methods delivered comparable performance, and the modified γ-framework provides a Eurocode-compatible basis for short-term design. • Full-scale bending tests on bonded TCC floors • Parametric study (geometry, stiffness, bond-line model): sensitivity for design • Global response: stiffness evolution, redistribution, failure mechanisms • Design guidance: stiffness prediction, shear effects, process quality control