Study on neutron shielding performance of high strength mortar modified by saturated super absorbent polymer

Abstract

In order to meet the requirements of nuclear safety, it is important to prepare mortars that simultaneously mortar with high compressive strength and neutron shielding properties. In this study, acrylamide-saturated super absorbent polymer (0.1, 0.2, 0.3%) was added to high-strength mortar to investigate its effect on neutron shielding performance. The influence mechanism of compressive strength, phase composition, and microstructure was analyzed, and the neutron radiation shielding performance of mortar was evaluated by Monte Carlo N Particle Transport Code (MCNP) simulation software. The results showed that the fluidity and hydration degree increased with the addition of super absorbent polymer (SAP), which increased by at least 10% and 27% compared with the control group. Proper addition of SAP can refine the pore structure of the matrix in the mortar. The highest compressive strength of mortar (113 MPa) was achieved when adding 0.1 %SAP of the total mass of the mixture. In addition, the addition of saturated super absorbent polymer significantly improved the fast neutron shielding effect of mortar, with a shielding rate 55% higher than that of normal mortar. For the same moisture content, SAP water-augmented mortar has the same shielding capacity as direct water-augmented mortar, but the compressive strength was improved by 19%.