Exploring the radiation shielding efficiency of low-impact Portland cement pastes made with barium sulfate, silica fume and fly ash

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

doi:10.15392/2319-0612.2025.2777

Authors

Maikon Moreira de Pires Universidade do Vale do Rio dos Sinos https://orcid.org/0000-0002-0231-9555
Everton Granemann Souza Universidade Católica de Pelotas https://orcid.org/0000-0001-9884-6626
Chiara das Dores do Nascimento Universidade Católica de Pelotas https://orcid.org/0000-0001-6028-9852
Larissa Carine Sobreira Universidade do Vale do Rio dos Sinos https://orcid.org/0009-0001-3887-8527
Isadora Zucchi Maia Universidade do Vale do Rio dos Sinos https://orcid.org/0009-0006-2205-5901
Henrique Trombini Universidade Federal de Ciências da Saúde de Porto Alegre https://orcid.org/0000-0002-7254-4774
Romulo Rocha Santos Hospital de Clínicas de Porto Alegre
Francisco Roger Carneiro Ribeiro Universidade Federal do Rio Grande do Sul https://orcid.org/0000-0001-8790-3023
Mauricio Mancio Universidade do Vale do Rio dos Sinos https://orcid.org/0000-0002-0736-7249
Claudio de Souza Kazmierczak Universidade do Vale do Rio dos Sinos https://orcid.org/0000-0001-7552-3867
Marlova Piva Kulakowski Universidade do Vale do Rio dos Sinos https://orcid.org/0000-0002-7661-3909

DOI:

https://doi.org/10.15392/2319-0612.2025.2777

Keywords:

Cementitious pastes, Barium sulfate, Protection barriers, Ionizing radiation, Radiotherapy

Abstract

The scope of this work is the development of new composites with low environmental impact to act as radiological shielding in hospital environments. For this purpose, the radioprotection properties of cement pastes containing 20% BaSO₄, in addition to 10% fly ash and silica fume as SCM’s were investigated. The samples were characterized by consistency, apparent density and mechanical strength at 7 and 28 days of age. In addition, transmission measurements were performed for different sample thicknesses using a photon beam from a linear accelerator operating at 6 and 10 MV in a radiotherapy room. The barium pastes showed a reduction in sample thickness of approximately 10% compared to the reference paste (without barium) at the highest voltage analyzed to attenuate 90% of the incident radiation (according to current legislation). Among the SCM’s, silica fume stood out as the most suitable substitute when combined with barium in Portland cement matrices. Finally, the apparent density of the samples appears to be decisive for the performance of new materials in terms of radiological shielding.

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