Reuse of wooden utility poles through the combination of new and old elements

Abstract

Wooden utility poles are crucial in supporting overhead telecommunication lines in Portugal. Maritime pine (Pinus pinaster Aiton) is the most common wood species used for this purpose. The durability of the poles is typically determined by the deterioration observed in their ground line. Aiming to reduce the use of new sound wooden poles, reducing the economic costs involved, and the environmental impacts, the reuse of those old wooden poles by removing the degraded part is one possible solution. This study aimed to develop and validate solutions with composed poles, specifically for the connections between the wood members, so that it is possible to more efficiently incorporate used parts into the remanufactured poles. Two types of connections were used: members joined by a cylindrical steel tube, and members joined by finger joints. The static bending moduli of elastic and rupture were tested. The mechanical properties of the reused wooden utility poles showed to be in line with the values of new sound wooden poles made of different wood species. Finally, both proposed solutions proved to be practical for use in the production of reused utility poles, which are mostly made from old timber poles.