Experimental research on mechanical properties of silica fume recycled concrete after freeze-thaw cycles
In order to ensure the safety of resource utilization of waste concrete produced by railway engineering in plateau area,the me-chanical properties of RAC after freeze-thaw cycles were studied by rapid freezing method.By changing the type of recycled coarse aggre-gate,replacement rate and silica fume content,the frost resistance of RAC and the mechanical properties after freeze-thaw cycles were studied.Through the change of RAC quality,dynamic elastic modulus,compressive strength and splitting tensile strength after freeze-thaw cycle,the influence of recycled coarse aggregate type,replacement rate and silica fume content was obtained.The results show that high strength recycled coarse aggregate can improve the frost resistance of RAC.When the replacement rate of recycled coarse aggregate is 50%,the frost resistance is the best.Silica fume can improve the frost resistance of RAC.