@thesis{thesis,
		author={Hendrawan  Hasan Bintang},
		title ={PEMANFAATAN BATU APUNG SEBAGAI SUBSTITUSI PARSIAL AGREGAT HALUS PADA BETON NORMAL},
		year={2019},
		url={https://eprints.ummi.ac.id/828/},
		abstract={The development in the field of construction in modern era shows rapid growth, so it demands the more and more innovative concrete technology. The Pumice in the manufacture of normal concrete is used for substitution materials in fine aggregates Adding pumice in a concrete mixture will make the weight of the concrete lighter. In this regard, a research was conducted using pumice as a substitute for sand in concrete mixtures of 10%, 20%, and 35%. The number of specimens is 3 pieces each. Testing of the mechanical properties of concrete was carried out at the age of 7, 14, 21 and 28 days, the tests included concrete compressive strength test, and concrete flexural strength. 
The results showed that the addition of 10%, 20%, and 35% pumice stone in the substitution of sand in concrete, was included in the category of normal concrete with an average volume weight of 2129kg / m3. The compressive strength of concrete decreases with increasing percentage of pumice, this is because pumice has a strong value crushed smaller aggregates compared to normal fine aggregates. Likewise, flexural strength decreased from normal variation to 10% and then increased again from 10% to 20%, and 35%. It can be concluded that the concrete with a red pumice mixture is more effectivelyused on bending beam elements in the structural of buildings or bridges.}
		}