NSUF 23-1884: Effect of neutron radiation on density and mechanical properties of white cement paste
The radiation induced volumetric expansion of minerals present in aggregates is a somewhat reasonably documented effect in irradiated concrete. Different minerals expand at different rates and amplitudes according to silica content, number of ionic vs. covalent bonds, and structural percolation of the silicate tetrahedrons; making silicates more susceptible to irradiation than carbonates. The coexistence of varied rock-forming minerals will result in mismatch strains, causing internal stress development and possibly irradiation-induced cracking that can percolate to the cement paste. While several studies have targeted the effects of gamma on the cement paste, very limited information is available on the effects of neutrons on the cement paste. Specially, the mechanical properties of the paste are of great importance to accurately model the degradation of concrete following neutron irradiation. Molecular dynamics simulations have predicted that there can be an atomic reorganization in the structure of calcium silicate hydrates, the main cement paste components, but no other studies are available on the effects of neutrons on the density and mechanical properties of the paste. We propose to measure the bulk and solid densities and the mechanical properties of neutron irradiated Japanese cement white pastes and compare them to their respective pristine counterparts. The methods we will use are dimensional and mass inspection for bulk density, He pycnometry for solid density and ultrasound pulse velocity for mechanical properties. The collected data will complement collected data of the same kind on Japanese aggregates of different mineralogy and will serve to further develop ORNL in-house predictive tools of concrete irradiation damage in MOSAIC to include a more accurate representation of the cement paste properties. The irradiated samples sustained doses are representative of those expected in LWR’s reactors after 80 years of operation and are thus relevant to support the ongoing license renewal of this type of reactors in the US. We require a total of 3 days of instrument time, that will be spread into a session of 3 days between February and March.
Additional Info
| Field | Value |
|---|---|
| Abstract | The radiation induced volumetric expansion of minerals present in aggregates is a somewhat reasonably documented effect in irradiated concrete. Different minerals expand at different rates and amplitudes according to silica content, number of ionic vs. covalent bonds, and structural percolation of the silicate tetrahedrons; making silicates more susceptible to irradiation than carbonates. The coexistence of varied rock-forming minerals will result in mismatch strains, causing internal stress development and possibly irradiation-induced cracking that can percolate to the cement paste. While several studies have targeted the effects of gamma on the cement paste, very limited information is available on the effects of neutrons on the cement paste. Specially, the mechanical properties of the paste are of great importance to accurately model the degradation of concrete following neutron irradiation. Molecular dynamics simulations have predicted that there can be an atomic reorganization in the structure of calcium silicate hydrates, the main cement paste components, but no other studies are available on the effects of neutrons on the density and mechanical properties of the paste. We propose to measure the bulk and solid densities and the mechanical properties of neutron irradiated Japanese cement white pastes and compare them to their respective pristine counterparts. The methods we will use are dimensional and mass inspection for bulk density, He pycnometry for solid density and ultrasound pulse velocity for mechanical properties. The collected data will complement collected data of the same kind on Japanese aggregates of different mineralogy and will serve to further develop ORNL in-house predictive tools of concrete irradiation damage in MOSAIC to include a more accurate representation of the cement paste properties. The irradiated samples sustained doses are representative of those expected in LWR’s reactors after 80 years of operation and are thus relevant to support the ongoing license renewal of this type of reactors in the US. We require a total of 3 days of instrument time, that will be spread into a session of 3 days between February and March. |
| Award Announced Date | 2023-02-08T10:48:38.263 |
| Awarded Institution | None |
| Facility | None |
| Facility Tech Lead | Kory Linton |
| Irradiation Facility | None |
| PI | Ippei Maruyama |
| PI Email | [email protected] |
| Project Type | RTE |
| RTE Number | 4573 |