Investigation of the radioactive content of cement based mortars

In this thesis, the effect of fine agregate type, cement, silica fume and fly ash on the radon exhalation rate and natural radioactive content of cement based mortar were studied. For this purpose, CEM I 42,5 R type Portland cement, 2 types of fine agregate (limestone and bazalt) and 2 types of mineral admixture (silica fume and fly ash) were used to cast 7 different mortar mixtures according to TS EN 196-1 standard. After the 28 days of curing, flexural and compressive strength, water absorption and water sorptivity tests were conducted. Besides, the radon exhalation in raw materials and mortar samples were measured by "Sealed can technique" using LR-115 type II track detectors and gama ray spectrometric measurements were used for the measurement of natural radioactivity (226Ra, 232Th and 40K). The obtained results showed that the radon and natural radioactivity of raw materials and mortars mixtures values were lower than the limit values recommended for the building materials used in construction of dwellings and the use of these materials in mortar does not pose any radiological risk.