Abstract

Diatomite is currently being used as raw material in various industrial sectors worldwide and is also in use in the construction industry, aimed at improving characteristics of concrete and cement, and in producing heat-insulating bricks, using various binders. In this study, usage of cement as a binder, in producing diatomite-based lightweight building elements, was investigated. Diatomite rocks were ground and sifted through sieves with square-shaped apertures of 500 µm then blended with cement at ratios of 10, 20, 30 and 40% by volume. The mixtures were kneaded to plastic consistency by adding water and were placed into the moulds to obtain test sample cubes of 100 × 100 × 100 mm in dimensions. Compressive strengths and ultrasonic sound transmission values of samples were determined as basic evaluation criteria. The samples were observed to have gained strength compared to the strengths of the samples of 7 days age at the end of 28 days curing period, and no visible deformations were determined for the first 50 days. However, as the age of the samples proceeded, the samples displayed decreases in their compressive strengths due to formations of capillary fractures that expanded gradually. Finally, at the age of 150 days, non-negligible mass losses developed in the samples. These loses were thought to have sourced from the alkali aggregate reaction that took place between cement and silica constituent of diatomite. Consequently, it was concluded that it is not convenient to use cement as a binding agent in the production of diatomite-based lightweight building elements.

Key words: Diatomite, aggregate, building materials, lightweight building component, binding agent, Cement, alkali reaction.