Evaluation of the Causes of Concrete Kerbs Fast Damage

Abstract

The paper presents the results of testing double-layered concrete kerbs with surface damage occurred after 3 years of construction. The testing was conducted to determine the causes of the fast destruction. The testing featured a visual inspection of the kerbs’ damage at the location of their construction and then sampling of 7 kerbs with various degrees of damage, which were transported to the laboratory. It was founded that in some kerbs the surface layer was damaged, whereas the concrete’s structural layer in all kerbs was in very good condition, without any damage. The testing program featured determination of properties, such as compressive strength, water absorption, capillary absorption and freeze-thaw durability – resistance to internal cracking and surface scaling. It was founded that the results of structural concrete testing: compressive strength, water absorption, freeze-thaw durability (resistance to internal cracking) and capillary absorption tests were not too useful in determining the kerb surfaces’ resistance to damage. Tests conducted using an optical microscope indicated that the concrete’s texture layer is insufficiently compacted. The test results indicate that the concrete’s water absorption (samples with the thickness of 50 mm, cut out from the kerb’s top surface) is best correlated with the test results the concrete kerb’s surface scaling in the presence of de-icing salts.