Shielding experiment for new concrete with high concentration of boron by using DT neutrons, 1; Development of new concrete with high concentration of boron

Shionaga, Ryosuke*; Nose, Hiroyuki*; Ito, Yuji*; Kato, Hiroaki*; Hashimoto, Hirohide*; Sato, Satoshi

In order to enhance the neutron shielding performance in nuclear power facilities, medical facilities and research facilities with large-scale accelerators, we have developed a new concrete with high concentration of boron of 10 weight %. Natural Colemanite minerals with a mass of boron were applied to the aggregates for the concrete. In addition, modification of the cement type and application of the special mixture material were performed to eliminate bad effects of the insufficient hardening and the strength degradation of the cement, and we successfully increased the boron concentration in the concrete up to 10 weight %. The flow rate in JIS flow test was about 150 mm before hardening of the material, which showed good flow property. We also confirmed that the compressive strength was about 40 N/mm at the material age of 7 days. Based on the results, the block specimens were fabricated for the shielding experiment using DT neutrons.