Hello everyone, I am currently working on a structural analysis of roof purlins (HUT shape), on which monocrystalline PV modules are mounted directly by screwing.
I am interested to know if anyone has experience with whether the stabilizing effect of the PV modules can be taken into account in the calculation. Specifically:
Are the modules allowed to be modeled as a rotationally supported surface (rotational support)?
Are there normative or practical indications as to whether the modules can contribute to the transverse stabilization of the purlins?
If the modules are modeled only as a load transfer surface, unrealistic deformations of the profiles occur.
Has anyone dealt with similar cases or can recommend literature/standards that deal with this topic?
welcome to our community. We are glad that you are active here.
As far as I know, within the scope of the Eurocode, only the rotational support and shear field effect through trapezoidal sheets for purlins are covered by the standard. If you want to use other elements for stabilization, you would need at least a scientific publication on this topic.
Are the solar modules actually mounted directly on the hat profiles, or is there an additional substructure?
thank you very much for your feedback. That’s exactly what I thought as well. I just wanted to ask here whether anyone has already designed similar systems and which engineering approach would be sensible.
The PV modules consist of aluminum frames and are attached directly to the HUT profiles (length approx. 2 m) with four self-drilling screws each. Some rotational capability is certainly given.
For better illustration, I have attached a sketch.
Thank you very much for the sketch. With this type of fastening, I would neither use a pivot bearing nor a thrust field. I had hoped for a continuous substructure from which one might be able to calculate a pivot bearing. But as it is, I would stay away from it.
