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PRECAST CONCRETE ELEMENTS116 CPI %u2013 Concrete Plant International %u2013 6 | 2025 www.cpi-worldwide.comIn order to ensure permanent drainage by tilting towards the building, a deflection limit of l/150 was specified. Using the dimensions in question, this would be 10.70 mm, which means that the deflection resulting from the live load is less than the specified limit. In addition, the system could be installed with an excess tilt for half the live load in addition to the permanent loads, resulting in even lower deflections.Furthermore, the natural frequency was determined by using a hammer test. Figure 7b shows a graphical representation of the vibration behaviour of the balcony slab as a result of a hammer blow. The settled system with a natural period T from t1 = 3.50 s to t2 = 3.62 s has a natural frequency f of 8.33 Hz and is therefore within a non-critical range for usage in residential buildings.Thermal insulationHeithorn investigated the insulating effect using a 3D thermal bridge calculation [3]. For this purpose, continuous thermal insulation made of rock wool with a thermal conductivity group WLG 035 and an insulation layer thickness of 160 mm was taken into account. His calculations yielded an equivalent thermal conductivity of %u03bbeq = 0.20 W/(mK). Compared to other systems, the insulating effect is thus approximately 5% lower despite the greater insulation layer thickness, but is still within the range specified by the building codes.PracticalityTo test the practicality of the system, a balcony with a width of 3.00 m and a total of 6 support points was constructed. The installation time for the brackets was evaluated. At a room temperature of around 20 %u00b0C, a single person was able to install and align all six brackets in around 20 minutes. The subsequent attachment of the balcony slab (Figures 8-10) was carried out without complications. The adjustment options shown in Figure 10 subsequently proved to be practical.The connected load test was unremarkable in terms of load-bearing capacity. The deformations were slightly higher than in the %u2013 except for the width of just 1 m - identical test. Fig. 7: Deformation under various loadings (a) %u2013 Frequency (b)Fig. 8: Balcony plate 3.00 x 1.50 m (a) %u2013 Hooking up (b) Fig. 9: Hanging process (a) to (d)a) b)a) a)c)b)d)b)