Mechanical performance of point-supported glass-glass BIPV floor tiles under ordinary non-uniform temperature and short-term sustained loads

Purpose This paper studies the response of building integrated photovoltaic (BIPV) floor tiles under normal thermo-mechanical conditions and superimposed short-term sustained loads. While the thin glass covers are in general minimally affected by ordinary thermal effects, the typical BIPV section suffers for possible loss of mechanical capacity, due to the sensitivity of the constituent materials, especially the encapsulant. Also, the features of fixing systems have further influence on the mechanical response. Design/methodology/approach 3D numerical models are inspired from real BIPV tiles and used to investigate the coupled thermo-mechanical performance of BIPV tiles under ordinary conditions. The effects of temperature variations are highlighted in terms of deflection, stress and bending stiffness. Findings Key mechanical performance indicators of typical use for laminated glass are critically discussed for the examined BIPV floor tiles. As shown, the serviceability deflection check of BIPV tiles is a key parameter of their performance assessment, which implicitly suffers from the progressive modification of the bending stiffness with increasing temperature. Originality/value Structural glass members are usually designed as load-bearing elements in terms of serviceability deflection and ultimate tensile stress verifications. One of the most influencing parameters in their mechanical analysis is represented by the shear flexibility of the interlayer in use to bond the glass panels. This aspect is even more pronounced for BIPV solutions, where both the glass covers and the encapsulant are subjected to non-uniform temperature scenarios due to ordinary heating, whilst their load-bearing role and mechanical capacity should be in any case preserved. This study shows the key role of thermo-mechanical considerations for similar systems, even under ordinary operational conditions.