الفهرس 
CHAPTER 1: INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
This study presents experimental work and theoretical analysis to evaluate the performance of heavyweight concrete for nuclear shielding applications. Heavyweight concrete mixes were prepared using different coarse aggregates including crushed dolomite, crushed magnetite and steel particles. Also, magnetite and steel filings were used to replace 50% and 100% by volume of the sand.
The workability of fresh concrete and the compressive strength at 7 and 28 days were evaluated. The gamma-rays attenuation coefficients for concrete samples were determined experimentally using gamma-ray spectrometry and theoretically using WinXCOM software at different gamma-energy lines of 0.662MeV (gamma source of cesium 137Cs), 1.173MeV and 1.332 MeV (gamma source of Cobalt 60Co).
The experimental results indicated that the concrete mixes containing steel particles as a coarse and fine aggregates achieved the most desirable performance in terms of density and gamma-attenuation. Concrete densities up to 5.8 ton/m3 were obtained using steel as coarse aggregates. For the examined photon energy lines, the average attenuation coefficient of the concrete mixes incorporating steel was two times that of the control mix. On the other hand, the concrete mixes incorporating magnetite achieved the highest compressive strength value of 68 MPa. The attenuation coefficient could be estimated theoretically using WinXCom with errors in the range of 12% to -15%.