EVALUATION OF NEUTRON SHIELDING MADE OF C EMENT TYPE MATERIAL

We prepared boron-containing cement and evaluated the characteristics of this new cement. This is the material of neutron shielding which is lighter than existing one. The quality we aimed is: H greater than or equal to 0.025g/cm(3), B greater than or equal to 0.065g/cm(3), densi ty less than or equal to 1.70g/cm(3). We made test pieces changing wat er powder ratio (W/P), adding amount of air entraining agent, adding a mount of water reducing agent, and time of vibration, and then, evalua ted the characteristics. The measured parameters are the air content, mortar flow and homogeneity for cement mortar, homogeneity and compres sive strength for hardened one. From the results of these tests, we co nfirmed the possibility of making neutron shielding that can satisfy t he aimed quality using this boron-containing cement. After all, we est ablished the method of making the neutron shielding, and this method w as used in the construction of RETF.