Title:
Thin Cement-based Composites for Efficient Neutron Attenuation (Prepublished)
Author(s):
Ashish D. Patel, Jerry M. Paris, Christopher C. Ferraro, James E. Baciak, Kyle A. Riding, and Eric R. Giannini
Publication:
Materials Journal
Volume:
Issue:
Appears on pages(s):
Keywords:
biological shield; boron carbide; high-density polyethylene; neutron radiation; portland cement mortar; radiation-induced volumetric expansion
DOI:
10.14359/51746803
Date:
5/8/2025
Abstract:
Prolonged neutron irradiation can damage concrete biological shields, particularly when nuclear power plants extend reactor lifespans. Retrofitting biological shields with thin and highly efficient neutron shields may limit neutron damage. Portland cement mortars amended with boron carbide and polyethylene powders were assessed for neutron attenuation. Shielding performance was compared to concrete with a similar design and coarse aggregate as a biological shield at an operational nuclear plant. Boron carbide enhanced the shielding performance of specimens under the full energy spectrum of the neutron source. Boron carbide and polyethylene synergistically enhanced neutron attenuation under a purely high-energy neutron flux. Engineered thin composite mortars needed 90% less thickness to achieve similar or better shielding efficiency as the concrete in a typical biological shield under the test conditions. Isothermal calorimetry, compressive strength, and thermal expansion results indicate that mixture design parameters of thin shields can be adjusted to achieve adequate structural properties without diminishing constructability or structural performance.