Explorando a eficiência da proteção contra radiação de pastas de cimento Portland de menor impacto ambiental elaboradas com sulfato de bário, sílica ativa e cinza volante
DOI:
https://doi.org/10.15392/2319-0612.2025.2777Palavras-chave:
Pastas cimentícias, Sulfato de bário, Barreiras de proteção, Radiação ionizante, RadioterapiaResumo
O escopo deste trabalho está no desenvolvimento de novos compósitos de baixo impacto ambiental para atuarem na blindagem radiológica em ambientes hospitalares. Para tanto, foram investigadas as propriedades de radioproteção de pastas cimentícias contendo 20% de BaSO4, além de 10% de cinza volante e sílica ativa como MCS. As amostras foram caracterizadas através da consistência, densidade aparente e resistência mecânica aos 7 e 28 dias de idade. Além disso, foram realizadas medidas de transmissão para diferentes espessuras de amostras utilizando um feixe de fótons de um acelerador linear operando a 6 e 10 MV em uma sala de radioterapia. As pastas de bário apresentaram redução na espessura da amostra de aproximadamente 10% em relação a pasta referência (sem bário) na maior voltagem analisada para atenuar 90% da radiação incidente (conforme legislação vigente). Dentre os MCS, a sílica ativa se destacou como o substituto mais adequado quando combinada ao bário nas matrizes de cimento Portland. Por fim, a densidade aparente das amostras parece ser decisiva para no desempenho de novos materiais frente a blindagem radiológica.
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Direitos autorais (c) 2025 Maikon Moreira Pires, Everton Souza, Chiara das Dores do Nascimento, Larissa Sobreira, Isadora Zucchi Maia, Henrique Trombini, Romulo Rocha Santos, Francisco Roger Carneiro Ribeiro, Mauricio Mancio, Claudio de Souza Kazmierczak , Marlova Piva Kulakowski
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