Effect of loss water during vibrations on the compressive strength of concrete fc’ 21.7 Mpa

Abstract

Abstract Concrete is an important material in construction because it is necessary to improve the quality of concrete. One of the quality of concrete is influenced by the presence of air cavities in the concrete. The air cavity in concrete can be reduced by vibrating. The vibrating air cavity in the concrete will rise to the surface in the form of water. The purpose of this study was to determine the effect of the amount of water that rises to the surface as a result of vibrations on the concrete compressive strength of fc’21.7 MPa. The method used in this research is the experimental method and the study of previous research theories. Vibration uses an external vibration method with the acceleration of 180 m/s2, variation velocity 160 mm/s, and displacement of 1000 mm. The time variations used are 1 minute, 2 minutes, and 3 minutes. The specimen is cylindrical, with a diameter of 15 cm and a height of 30 cm. The results showed the highest amount of water that was on the surface contained in the vibration with a time of 3 minutes with a compressive strength of 23.35 MPa and water content 0.78 gr.