Experimental study on shell-strengthening the lightweight pumice aggregates

Natural pumice aggregates have the characteristics of low numerical tube pressure and high water absorption, in this study, the pumice aggregates was reinforced by making shell process with the methods of mixing pumice powder and silica fume into cement, which aimed to solve the problem that it was difficult for the preparation of lightweight concrete of high strength . Through the strengthening treatment of pumice aggregates, the light aggregates with the numerical tube pressure of 2.6Mpa bulk density less than 500 kg/m³ and water absorption ranging from 12.1% to 17.5% were obtained. The lightweight aggregate concrete was also made up with pumice. The compressive strength of the concrete at 28d age was higher than 15MPa and the apparent density was about 1400 kg/m³. So the results of this research were conducive for the preparation and application of high-strength and lightweight pumice concrete.