In fact, already from our beginnings in 2013 we realized that it was essential to first establish which were the most appropriate basic parameters, to be used in the sizing of a photovoltaic field on a flat surface: it may seem obvious or trivial, but this is the main problem to be solved.
The DM in fact divides the types of roofs into: pitched roofs, flat roofs, canopies and shelters, sheds.
So, the first question to answer is: which of these types most resembles a photovoltaic field with a tilt (angle) not coplanar to the roof?
Taking a cue from the DM 14/01/2008, we realized that the best way to establish the CP (pressure coefficients) on the first row most exposed to the wind was the one indicated for flat roofs. Then applying the thrust to the various rows, the parameters used on the shed roofs were considered, but without using the progressive decrease of the Cp between the rows, foreseen by the DM which would have brought the thrust coefficients to very low values, in our opinion not applicable.
Last but not least, we had to take into account the load increase on the roof (Kg / m2), making sure not to exceed the parameters above which the seismic verification is required.
In conclusion, the real challenge was finding the right balance between strength and weight of the structure: for this reason, an approximate approach such as “when in doubt I put more weight” would not have led to a functional and safe solution.
So, with a series of tests in the Wind Tunnel, both on real-size elements and on reduced-scale building models, as well as simulations in fluid dynamics, we have gained in-depth know-how based on real experiences, on which we base our sizing produced by our technical support during the estimate phase.
This same know-how acts as a generating line in the design and prototyping phase of new models.
With this approach, using the Research and Development division as a forerunner and a beacon in still unexplored areas, in seven years of activity we have gone from two to more than forty models. With two new patents filed.
And today Sun Ballast® can boast the widest range of solutions for structures on flat surfaces offered on the European market and beyond.