Concrete Stamps

Grades of concrete on frost resistance of the F 25 and F 500 is characterized by the number of cycles withstand alternate freezing and thawing in water-saturated state. Concrete Stamps on water resistance of W 2 and W 12 is characterized by the limiting pressure at which the water is still not observed seeping through her test sample. Grades of concrete on the density of D 800 and D 2400 is characterized by high density (kg/m3). Physical methods of control of concrete quality are developing based on the achievements of electronics, acoustics, radiometry and differ in that they do not require the destruction of the material, and can be repeatedly reproduced. The physical methods of testing concrete include pulsed ultrasound, resonance and radiometric. When the electron-acoustic test methods used between the rate of propagation of elastic waves in concrete and its mechanical properties. The most common pulse ultrasonic devices.

The speed of ultrasound on the properties of aggregates, concrete moisture and other factors. Therefore, the graph korelyatsionnoy links 'strength of concrete – the speed of ultrasound' (Rb – V) is being built for a specific composition of the concrete filler at this: Control concrete samples or cores, drilled from the structure prozvuchivayut ultrasound, and then tested in the standard for determining the strength. The ultrasonic method can detect the quality of concrete products and structures. By measuring the speed of propagation of ultrasound in different parts of the design, we can estimate the homogeneity of the concrete, without resorting to testing concrete samples. Concrete must be uniform – it's the most important technical and economic requirements. To assess the homogeneity of the concrete This marks use the results of control testing of concrete samples for a certain period of time. It is understood that the standard samples hardened in the same conditions at the same time. The strength of concrete samples will fluctuate, deviating from the average up or down side. Impact on the strength of fluctuations as cement and aggregates, dosing accuracy components, the care the preparation of concrete mix and other factors.