Experimental study on sodium-concrete reaction mechanism in sodium-cooled fast reactor

Kikuchi, Shin  ; Seino, Hiroshi ; Ohno, Shuji  

For countermeasure against sodium leak, structural concrete is protected by steel liner in a sodium-cooled fast reactor (SFR). However, if considering severe and unexpected accidental condition such as breach of steel liner by intensive sodium leak, the reaction with liquid sodium and concrete potentially may occur. For the purpose of elucidating the mechanism of the sodium-concrete reaction in SFRs, kinetic study of the sodium (Na)-silica (SiO) reaction has been carried out by Differential Scanning Calorimetry (DSC) technique. The Na-SiO reaction temperaturewas identified from DSC curves. It was found that reactivity of Na-SiO reaction is similar with the reaction between Na and aggregate of practical used concrete. Based on the measured reaction temperature, rate constant of Na-SiO reaction was obtained. Thermal analysis results indicated that Na-SiO reaction could occur under the elevated temperature in the timeframe of sodium-concrete reaction.