Short-term bending test of prestressed CLT-concrete composite panels

An adhesive shear connection of timber and concrete enables the production of a composite structure with relatively high bending resistance. A wet method of glueing allows fresh concrete and mass timber slabs with a not ideally planar or a curved surface to connect. In this method, the shrinkage of concrete negatively impacts the long-term behaviour of composite panels and causes relatively high deflection. This negative effect was eliminated in the production of prestressed CLT-concrete composite panels using a high initial camber of CLT slab before concreting and shear connecting with the concrete slab. The camber values were at the level of 1/100 of span. This paper presents the results of a short-term bending test of two prestressed CLT-concrete composite panels. The test was performed one year after concreting. The results confirmed the presumption that by prestressing the panels, it is possible to achieve higher load-bearing capacity compared to the load capacities of non-prestressed panels.