In the article the ultrasonic testing of cement floors to evaluate the compressive strength along the thickness has been presented. Testing has been performed on the samples obtained from cut sections of cement floors with various thickness. The study was performed non-destructively with the use of special ultrasonic heads with pointing contact to the surface. A correlation between the longitudinal ultrasonic wave velocity and the compressive strength of the cement mortar incorporated in the floor has been established. The obtained results were compared with the results of the destructive tests carried out in the strength machine. It has been shown that in the upper area of the cement floor the compressive strength is lower than in the lower zone. It is also lower in the central zone, but close to the results from the destructive tests. Bearing in mind the results of the research, attention has been paid to the possible remedial actions that can contribute to the proper maintenance of the floors.

Keywords: cement floors; horizontal forming; compressive strength; ultrasonic testing.