Abstract: The continuous development of national infrastructure gave rise to a large amount of construction and demolition waste.The utilization of construction and demolition waste as a resource is not only economical and environmental friendly,but also relieves environmental pressure.The dynamic properties of construction and demolition waste soil and sand were examined by large-scale indoor dynamic triaxial test.The stress-strain,time history curve,dynamic elastic modulus,and damping ratio were analyzed,and liquefaction was evaluated.Test results demonstrate that the damage dynamic stress of construction and demolition waste is about 1.3 times that of sand.In other words,the bearing capacity of construction waste soil is obviously higher than that of sand.Under cyclic loading,the excess pore water pressure of sand is about 2.5 times that of construction and demolition waste soil;therefore the liquefaction of construction and demolition waste soil is less possible.The dynamic elastic modulus of construction and demolition waste soil is much higher than that of sand,reaching 1.3 times that of sand.In conclusion,construction waste soil has better performance than sand,hence has the potential to replace sand as filling material for road engineering.

Key words: construction waste soil, sand, large-scale indoor dynamic triaxial test, dynamic characteristics, liquefaction analysis