Bài báo khoa học

In the present work, the squeeze flow techniques were used to investigate the influence of squeezing rates to the yield stress of different cementitious materials, including mortars and cement pastes. Tested samples were prepared under similar conditions of room temperature and atmospheric pressure. Compositions of motars and cement pastes were tested at three squeezing rates (20 and 200 mm/s) 15 min after mixing. The results indicate an increasing in the material’s yield stress with the rising of the squeeze velocity. This increase is evident at low tensile speeds (2 mm/s) and fast pulling speeds (200 mm/s). At an average speed of 20 mm/s, this increase is not obvious. It shows that the pressing speed in construction period has a significant impact on the ability to remove the mortar and the upper surface (masonry bricks, tiles adhesive, etc). High squeezing speed will increase the ability to resist peeling of materials when sticking to mortar.