Korelacija radioloških i strukturnih karakteristika građevinskih materijala

Abstract

U ovoj doktorskoj disertaciji predstavljena je radiološka i strukturna karakterizacija građevinskih materijala koji se mogu naći u upotrebi u Srbiji. Izvršena je radiološka karakterizaicija ukupno 348 uzoraka: granita, fosfogipsa, sirovina u keramičkoj industriji, keramičkih pločica, betona, opeke, maltera, siporeksa, crepa i drugih građevinskih materijala opšte upotrebe. Radiološka karakterizacija je sprovedena merenjem koncentracija aktivnosti 226 Ra,232 Th i 40 K metodom gama spektrometrije, kao i ekshalacije radona iz selektovanih građevinskih materijala korišćenjem aktivnih uređaja RAD7, RTM 1688-2, AlphaGUard i AlphaE. Korišćenjem Monte Karlo simulacija izvršena je procena jačina apsorbovanih doza gama zračenja, uočena su odstupanja od teorijski procenjenih vrednosti i dati predlozi za korekciju. Izvršena je procena radijacionog rizika od korišćenja analiziranih građevinskih materijala u enterijeru, kao i za profesionalna lica pri radu sa sirovinskim materijalima. Ispitivane su mogućnosti upotrebe fosfogipsa kao NORM materijala u proizvodnji gips-karton ploča i opeke uz procenu radijacionog rizika od upotrebe. Napravljeno je 8 uzoraka opeke sa različitim udelog fosfogipsa i izvršena je radiološka i strukturna karakterizacija dobijenih materijala. Ispitivane su varijacije koeficijenata emanacije radona iz građevinskih materijala tokom vremena, kao i uticaj efekata curenja i povratne difuzije koji dovode do tih varijacija. Ispitivan je takođe i uticaj strukture materijala u smislu mineraloškog i hemijskog satava i poroznosti na vrednosti koeficijenta emanacije radona. Meneraloška karakterizacija uzoraka izvršena je metodom rendgenske strukturne analize (XRD), a hemijska metodom rendgenske fluorescentne analize (XRF). Merenje ukupne efektivne poroznosti izvršeno je metodama apsorpcije vode i metodom živine porozimetrije. Na osnovu dobijenih rezultata uspostavljene su značajne korelacije između pojedinih radioloških i strukturnih parametara za analizirane uzorke građevinskih materijala.

In this doctoral dissertation, the results of the radiological and structural characterization of building materials used in Serbia were presented. Radiological characterization of a total of 348 samples was performed, including granite, phosphogypsum, raw materials in the ceramic industry, ceramic tiles, concrete, brick, mortar, siporex, tiles, and other materials frequently used as building materials.Radiological characterization was performed by measuring activity concentrations of 226 Ra,232 Th, and 40 K by gamma spectrometry method, as well as radon exhalation from selected building materials using active devices RAD7, RTM 1688-2, AlphaGuard and AlphaE.Using Monte Carlo simulations, the absorbed gamma dose rates were estimated. Furthermore, the deviations from the theoretically estimated absorbed dose rates were observed, and suggestions for correction were given. An assessment of the radiation risk from the use of analyzed building materials in the interior, as well as for occupational workers working with raw materials was conducted.The possibilities of using phosphogypsum as a NORM material in the production of gypsum plasterboard and bricks were investigated, with an assessment of the radiation risk due to use of phosphogypsum as a component in the building materials. 8 samples of bricks with different proportions of phosphogypsum were made and radiological and structural characterization of the obtained materials was performed. Variations of radon emanation coefficients from building materials over time, as well as the influence of leakage and back diffusion effects leading to these variations, were investigated. The influence of the structure of the material in terms of mineral and chemical composition and porosity on the values of the radon emanation coefficient was also investigated. The mineralogical characterization of the samples was performed by the method of X-ray structural analysis (XRD), and the chemical characterization by the method of X-ray fluorescence analysis (XRF). The measurement of total effective porosity was performed by water absorption methods and mercury porosimetry method. Based on the obtained results, significant correlations were establishedbetween individual radiological and structural parameters for the analyzed samples of construction materials.