Study On Carbonation Of Hybrid Fiber Reinforced Concrete

Low and medium radioactive nuclear waste for permanent storage repository unit capacity of the concrete structure,the service for 300 years,sustainability of the natural environment erosion,due to long-term carbonation will decrease the material performance of concrete deterioration,strength,and can lead to neutralization of concrete,rebar corrosion,and concrete cracking.Therefore,carbonation on the security function pose a threat.Considering the influence of long-term natural environment to its durability,because the external environment can not change,so can only proceed from the material itself,reduce the internal defects and imparove the structure of the concrete.The carbonation durability of steel polypropylene fiber reinforced concrete(SP)and basalt polypropylene fiber(BP)was studied by using ordinary concrete(C)as control group.Through the system analysis of concrete carbonization and control group of The compressive strength,splitting tensile strength,elastic modulus,ultimate strain and stress strain curves of the change,to clarify the nature of the carbide on mechanical properties of concrete material.Based on accelerated carbonation experiment,the establishment of the fiber reinforced concrete carbonation depth prediction model,in view of the different from the actual project environment factors and environmental factors is modified,the applicable to practical engineering in the carbonation depth prediction model;to explore the different criterion of carbonation life conditions of use,according to the functional requirements of the permanent nuclear waste storage and selection of corrosion cracking life criterion,of fiber reinforced concrete corrosion cracking life was revised and to predict the life.The results show that the microstructure and mechanical properties of the concrete are imparoved by the incorporation of fiber,and the anti carbonation and carbonation life of the concrete are imparoved.