Pressure distribution analysis

As the data shows, gypsum capping provides an ideal test surface with complete flatness perpendicularity and horizontality.Therefore it can reach the highest compressive strength value and retain stable data at anytime.

The flatness can reach as low as 2.7 μm.(see the fig.2) The complete smooth surface is coming from the flowing gypsum slurry and thick glass plate. After covered by the glass, the gypsum surface will get flat just like the glass similar to a mirror.

Fig.1:Gypsum Capping pressure uniformity: It provides a perfect load distribution

Grinding pressure uniformity: It shows a obvious knife pattern

Grinding method merely shows similar flatness to the bottom end. The concrete surface is treated by the grinding knife. It is difficult to get a completely smooth surface. Without the periodic maintenance, the knife has high possibility to get damaged then may cause a poor end surface.