Potential use of kelud volcano eruptive deposits, Indonesia as aggregates of Green structural lightweight concrete.

The study presents the potential use of Kelud volcano eruptive deposits, Indonesia which includes river sand as fine aggregate, pumice as well as scoria as coarse aggregate of green structural lightweight concretes. Their physical properties were experimentally tested and compared with controls that were commonly used in the region. Furthermore, they were applied on pumice and scoria lightweight concretes designed for five determined compressive strengths and compared with normalweight concrete as a control. The physical properties of fresh and hardened concretes as well as the mechanical properties were also investigated experimentally. Precast slab units of both lightweight concrete were used as their structural application and evaluated for their maximum bending capacity, stiffness and self-weight then they were also compared to the control. The results stated that the river sand, pumice as well as scoria fulfilled the fine and coarse aggregate requirements for lightweight concrete. The pumice and scoria lightweight concretes obtained were the structural lightweight concretes with the compressive strengths were approximately 30 MPa and the density reductions were about 22%. For the similar determined compressive strength, the maximum bending capacities of both lightweight concrete precast slab units were quite high and the self-weights at 28 days were about 85% lower than the control. However, the stiffnesses were lower than the control so that their deflections must be considered in the design. [ABSTRACT FROM AUTHOR]