Siguranța în exploatare a stâlpilor din beton armat aferente liniilor electrice - analize de caz.

By visual observations the degradation of reinforced concrete pillars for the support of electricity distribution lines was analysed. Following electrochemical and electrical measurements on the field, as well as some pH determinations and microbiological identification of mold species on degraded concrete samples, it was found that the advanced degradation state of the investigated pillars is due to the total de-alkalinisation of the concrete (7 <PH <8.5) which made possible the advanced corrosion of steel bars (Ecorr> 0.315VCu / CuSO4). Corrosion of steel bars and degradation of concrete was accelerated by polarization in A.C. (1.26Vrms between steel bars and ground, signal with high harmonic content - maximum value of 4.3Vpp being obtained at harmonic III). In the degradated concrete samples, the Trichoderma viride, Chaetomium globosum and Aspergillus niger species have been identified. [ABSTRACT FROM AUTHOR]