Study on the properties of aggregates used for production of ribbed slab hcb in Ethiopia

Abstract

Concrete can found everywhere around the world. It has dominated world multi-story commercial and residential building. Slabs take the highest cost Percentage of the total volume over the other structural load bearing Members. Nowadays, one of the most common floor systems is ribbed slab concrete. The conventional available hollow concrete block size results its limitation on the concrete slab thickness. Hollow blocks construction provides facilities for electrical conduit, water and soil pipes. It saves cement in construction work, bringing down cost of construction considerably. The objectives were study on properties of aggregates used for production of ribbed slab HCB in Ethiopia.To identify the physical property of aggregates and compare the result with different standards. The other objective were to find out effect of each different aggregates property on production of ribbed slab HCB .The effects are expressed by using compressive strength, density of the block and dry shrinkage tests and compare the result with ES. The aggregates are classified based on density: pumice, red ash (scoria)and crushed (01) aggregates.The HCB used in this study are casted using prelisted aggregates and combination of those three aggregates.. The studywas conducted in terms of quantitative methods. The study designs used for this research were comparative and lab based study. The laboratory test was conducted compressive strength of HCB agefor 7, 14 and 28 day. From the result crushed aggregate had highest specific gravity than pumice and red ash aggregate.It indicates low porosity therefore high durability and high strength had gainThe water observation of Crushed aggregate was lowest value .Which indicated that during mix design, water cement ratio would depended on this value.Mixed of three aggregate had largest compressive strength relative to crushed ,red ash and pumice HCB. Their Compressive strength respectivelyare 2.3, 2.13, 2 and 1.95 Mpa.