In last days I noticed some gathering of some like small pieces of soil or some small debris close to the wood part of building. I start to think that it is not only dirty brought by rain and wind. Today I've studied them closer and I think that they appear as termites pellets.
I think they are Dampwood termites pellets but I need a confirmation.
Many pellets look like a bit of an almost half longitudinal section of a tube with thick walls. A tube with not very finished/clear shape. Size, just an estimation, comparable/less 1 mm.
I noticed this pellets in two places relatively close each of other but well separated. These places are pretty exposed to rain and in last time the weather was rainy. Here the wood are close to the concrete floor but not have contact with the ground. Not built tube to connect the wood with the ground. These facts make me to think to Dampwood termites - Zootermopsis, and to rule out Drywood termites.
Close to these places I found this one but I didn't see others and I thought that was just an isolated accidental occurrence. The above mentioned pellets was not yet.
Note: By comparing to some photos found on net, I suppose that the pellets from my photos are spread due to rain water or to wind. But the pellets appears to be concentrated where they are the best conditions to maintain the wood moisture (moisture due to the rain).