Shielding concretes, the use of some additives in making shielding concrete

Abstract

This research has been done in order to define the linear attenuation coefficient of barite concrete and its other physical properties. First of all, a standard mixture is obtained and tested, then the concretes are prepared by using ; retarder, waterproofing admixture, plasticizer and also colemanite; are tested. The results of concretes with additives are compared with the results of standard mixture.In the preparation of samples great attention is spent to be the amounts of slump and cement is fixed. When ordinary sand is used instead of barite sand it is seen that compressive strength of concrete increases and linear attenuation coefficient decreases by 13%. The effect of workability increasing admixture to the compressive strength and linear attenuation coefficient, was observed as negligible.This observation is valid also for the retarder. Waterproofing admixture increased the compressive strength and the linear attenuation coefficient by a considerable amount. It is found that the negative effect of colemanite in cement setting can be decreased by increasing the cement dosage; at the same time colemanite has not an accountable positive effegt on gamma ray shielding. but there will be an important place on neutron shielding More detailed knowledges, graphs and the explanation of the test results will be given in their respective chapters.