The Barite Radiation Concrete Mix Than The Design And Performance

Radiation shielding barite concrete is more importantly to shield rays in addition to meet some general functions.The application of the radiation shielding barite concrete shall be expanded gradually as the development of nuclear reactor technology and the implementation of national long-term nuclear power policy. The method of experimental research and theoretical analysis was adopted to make systematic research on raw material and its performaces,mix design, perfomace of radiation shielding barite concrete as well as construction technique and process parameters.Relative Settlement Coefficient was put forward as evaluation index on anti-segregation for its easy segregation.The results of research showed that:(1)The production of radiation shielding barite concrete should adopt cements with higher density, more combining water and lower hydration heat. The apparent density of chosen barite aggregate shall meet the standard of apparent density of concrete, coarse-fine aggregate gradation should be continuous gradation which shall be adjusted when it was bad. (2) The apparent density of radiation shielding barite concrete had a lineal relation with apparent density of aggregate which went down with increasing water demand. Compared with the mix design of common concrete, radiation shielding barite concrete should choose suitable barite raw material first. Water demand can take that of general concrete as reference. When reached the same slump,it should be 5kg/m3 smaller. The sand ratio shall be added by 3%-5% on that of general concrete. When mixing with general sandstone aggregate, the apparent density of barite concrete went down.Mixing with general coarse aggregate can raise the strength of concrete which changed unclearly when mixing with general fine aggregate.(3)Relative Settlement Coefficient can be used to evaluate the capacity of Relative settlement and anti-segregation of radiation shielding barite concrete aggregate.The bigger Relative settlement Coefficient,the worse its anti-segregation.(4) The compressive strength of radiation shielding barite concrete and water-cement ratio accorded with Bolomy Formula, cement-water ratio and strength had good linear correlation. Correlative analysis was made to getαa=0.50,αb=0.35;axes compressive strength was 75%-80% of cubic compressive strength; splitting tensile strength was 6%-8% of cubic compressive strength; elastic modulus was smaller than general concrete of the same strength grade. (5)When radiation shielding barite concrete was at 100℃,loss of internal water was heavy while loss of strength was smaller. Its linear expansion coefficient was bigger than that of general concrete and when temperature was below 80℃, linear expansion coefficient could be (1.6-2.0)×10-5/℃;(6) Cellulose thickener can obviously improve workability of radiation shielding barite concrete, prevent segregation and bleeding, but lower anti-radiating capacity and strength of concrete, the best mixing amount was 0.05%.(7)The big apparent density and easy segregation of radiation shielding barite concrete should be paid much attention so as to guarantee construction quality of concrete through complete construction scheme.