Abstract:
Normal weight concrete of sufficient thickness is used for shielding and protecting buried structures. However, it is desirable to use heavy weight concrete to permit reduction of the size and thus to provide more working space. Such high-density concrete could be produced by the use of heavy weight aggregates. It could be made by adding a considerable proportion of based iron aggregates such as ilmenite. Analyzing and investigating the performance of heavy composite concrete media upgraded with adding rice husk ash (RHA) was the aim of this research. The coarse aggregate – ilmenite – was supplied in small sizes. An effort has made to overcome the disadvantage of small coarse ilmenite aggregate by adding gravel. The mix with ratio between Ilmenite: Serpentine: Gravel as 1:1:1 respectively gave better responses. It would be better than the other tested mixes to give the best mechanical properties with reasonable unit weight. The RHA is highly reactive pozzolanic material and can be used as a supplementary cementing material. The concrete containing 10% RHA - as a replacement for a part of the ordinary Portland cement - had higher compressive strengths at various ages up to 180 days compared with that of the mixes without RHA. Adding 10% RHA has a positive effect on mixes as they contained to gain strength concerning the values of compressive strength for a long period of time. It has no clear effect to enhance the tensile strength or the unit weight of mixes.