Ocena stanu technicznego betonowych pokryw studni kanalizacji kablowej stosowanych w ciągach drogowych

The subject of the paper is the technical condition of precast concrete covers of cable manhole used on roads for pedestrians and vehicles. The purpose of performed investigation was the evaluation of the technical condition of concrete covers on the basis of visual inspection of existing precast covers and analysis of quality of concrete used for precasting. Multiple covers were observed to be defective already after one year of exploitation. Frequent mistakes of installation of corers were also found. A large scatter of compressive strength of concrete was found and the strength of concrete in about 15 % of specimens was found to be lower than 25 MPa required for the lowest class of A 15 covers.