Mechanical and radioactivity shielding performances of mortars made with cement, sand and egg shells

All living things and inanimate objects, i.e., humans, animals, plants, air, water and soil, both emit and are exposed to natural and artificial radiation. The main objective of this study was to evaluate the feasibility of the use of industrial egg shell waste for the protection of buildings against external radiation effects. Towards this end, the radiation absorbing property of mortars made of cement, Rilem sand and egg shells was extensively studied. During this investigation, the possible decrease in the quality of mortars like 90-day sulfate resistance and the 7, 28 and 90 day compressive and flexural strengths were also investigated. The results showed that egg shells as an additive decreased the compressive and flexural strengths of the mortars for all the samples with different additive percentages of egg shells for all ages. However, the mix proposed satisfies the minimum compressive strength requirements of the Turkish standards. The linear absorption coefficient increased in the samples with increasing egg shell ratio, i.e., mortars with egg shells had low radioactive permeability. Hence, egg shells may be used in regions where radiation is effective. Such concrete can easily be used in walls for radiation shielding. (C) 2015 Elsevier Ltd. All rights reserved.