Gamma and neutron attenuation properties of alkali-activated cement mortars


Canbaz Öztürk B. , Kızıltepe C. Ç. , Özden B. , Güler E., Aydın S.

Radiation Physics And Chemistry, cilt.166, ss.1-9, 2020 (SCI İndekslerine Giren Dergi) identifier

Özet

Radiation-shielding properties of alkali-activated cement (AAC) mortar mixtures prepared using different precursors

such as ground granulated blast furnace slag (GGBFS), fly ash (FA), metakaolin (MK) and waste clay

material containing boron (WCB) were investigated comparatively with Ordinary Portland Cement (OPC)

mixture. The gamma linear attenuation coefficients of the mixtures were determined both experimentally and

theoretically. The experimental coefficients of the mixtures were measured with NaI(Tl) detection system for

gamma energies of 137Cs (662 keV) and 60Co (1173 and 1332 keV) and the gamma transmission parameters

(half-value layer, HVL; tenth-value layer, TVL and mean free path, MFP) were determined using these coefficient

values. The theoretical coefficients of the mixtures were calculated using XCOM software for the energy range of

10–3000 keV. In addition, neutron attenuation coefficients of the mortar mixtures were theoretically calculated

with the NCNR computation software for thermal (0.025–1 eV), slow (1–10 eV), resonance (10–300 eV), intermediate

(300 eV-1 MeV) and the fast neutrons (1 MeV–20 MeV). Test results indicated that GGBFS and FA based

alkali-activated cement mortars had similar gamma attenuation properties to the OPC mortar while the WCB and

MK-incorporating AAC mixtures had slightly worse properties in this respect. In terms of thermal and slow

neutron shielding properties only AAC mixtures containing WCB showed significantly better behaviour compared

to OPC. For neutrons having higher energy levels than slow neutrons, all AAC and OPC mortar mixtures

showed comparable properties.