Boundary conditions for adhesive joints in façade cladding elements

The object of research is adhesive fastenings in façade metal cassettes of hinged façade systems. This work aims to develop a simplified method for defining boundary conditions of adhesive fastenings of façade cassettes in numerical models. Method. Experimental tests of adhesive tapes were carried out to determine the estimated elastic modulus, load‑bearing capacity, and failure mode. Finite element analysis of façade metal cassettes was performed using different approaches to modelling adhesive joints to assess their influence on the structure's stress-strain state. Results. A preliminary value of the elastic modulus of the structural adhesive tape (375 kPa) and the average failure stress (548 kPa) were obtained. Failure exhibits a mixed adhesive-cohesive character and depends on the loading rate. Replacing silicone sealant adhesive with structural tapes has almost no influence on cassette deflections (2−4%). Numerical models showed that adhesive fastening can be represented as hinged contacts without explicitly modelling solid geometry. Load-width participation factors were determined for various span configurations, and a formula was proposed to calculate stresses in adhesive joints under wind loading.