Research On Bionic Self-Cleaning Cement Stabilized Macadam Permeable Base

To overcome the problems of pores blockage and water damage of commonly used skeletal void type cement stabilized macadam permeable base of permeable pavement,this research carried out a study on self-cleaning and water-resistant permeable base of skeletal void type cement stabilized macadam based on bionic 3D super-hydrophobic modification.Firstly,bionic super-hydrophobic modifying agents were developed to realize the surface and 3D overall super-hydrophobic modification of cement binder used in cement stabilized macadam.Secondly,the microstructure,crystal structure,molecular groups and chemical elements of cement binder used in bionic super-hydrophobic modified skeletal void type cement stabilized macadam were studied with material microscopic chemical characterization technologies.Based on the molecular dynamics theory,a molecular dynamics model was established to study the nano-mechanism of biomimetic super-hydrophobic modification,and then the micro-nano-mechanism of biomimetic super-hydrophobic modification of cement binder used in bionic super-hydrophobic modified skeletal void type cement stabilized macadam was revealed.Finally,the mechanical properties,self-cleaning properties,water damage resistance,wear resistance and permeability resistance of super-hydrophobic modified skeletal void type cement stabilized macadam were studied.The results showed that:(1)The strength of super-hydrophobic modified cement based material decreased to a certain extent,but its toughness increased slightly;(2)Super-hydrophobic modified cement based materials have excellent self-cleaning ability,which can significantly improve the anti-clogging ability of skeletal void type cement stabilized macadam;(3)Super-hydrophobicity modification can shorten the frequency and duration of "three-body" lubrication effect on the interface of cement binder between aggragetes of skeletal void type cement stabilized macadam;(4)Compared with surface super-hydrophobic modification,3D whole super-hydrophobic cement-based material has stronger wear resistance;(5)Super-hydrophobic modified cement based materials have significant anti-permeability effect,which helps to improve the service durability of cement based materials in the presence of water.The results of this study can provide technical support for the durable skeletal void type cement stabilized macadam permeable base used in permeable pavement of sponge city.