De-aluminated metakaolin-cement composite modified with commercial titania as a new green building material for gamma-ray shielding applications

Sustainable disposal of dealuminated metakaolin (DAK) is a crucial environmental issue for the alum production industry. In previous studies, DAK was utilized as eco-friendly cementitious materials, but only 10 wt% used instead cement DAK's high percentage has detrimental effect on mechanical properties, so problem not yet been solved. this study, commercial titanium oxide (TiO2) incorporated in matrix containing that reached 50 to benefit from TiO2's properties enhancing performance binding materials and producing blends blocking against harmful gamma radiation. Five pastes were prepared reach main target; ordinary Portland (OPC), OPC-10%DAK (D10), OPC-30%DAK (D30), OPC-50%DAK (D50) OPC-45%DAK-5%TiO2 (D45-T5). By means mini-slump test, all fresh have very close flowability using appreciated additions polycarboxylate superplasticizer. The hardened composites cured tap water up 28-days. Compressive strength results at 28 days OPC, D10, D30 D50 80, 94.6, 60.8 57.6 MPa, respectively. An obvious turning point value 88 MPa after replacement by 5 TiO2 A gamma-ray shielding test performed two radioactive isotopes (Co-60 Cs-137). inclusion 5% great impact development power D45-T5 compared with OPC; linear attenuation coefficient (µ) values enhanced 0.127 ± 0.003 cm−1 0.199 0.007 661.6 Kev 0.118 0.144 0.005 1332.5 Kev. unique specimens anatase phase may be attributed fact act nano-filler active seeds formation further hydration products such CSHs, CAHs CASHs detected X-ray diffraction (XRD), thermal analyses techniques (TGA/DSC) scanning electron microscope (SEM/EDX). caused rearrangement textural structure composite meso pores, proved N2-adsorption/desorption technique. Moreover, TiO2’s tetragonal makes it dosimetric characteristics adsorbent rays.