Effect of Cyclic Clogging-Cleaning on Water Permeability of Porous Asphalt Mixture

In order to study the anti-clogging performance of porous asphalt pavement, the porous asphalt concrete (PAC) was clogged with aeolian sand as a clogging material, and the PAC specimens after each clogging were cleaned by manual brushing, vacuum pumping and high-pressure water washing. The permeability of each specimen after clogging and cleaning was measured using falling-head permeability setup. The effect of air voids, nominal maximum aggregate size and cleaning method on the permeability of PAC under the condition of cyclic clogging-clea-ning was investigated. Based on this, the clogging sensitive particles of PAC-13 were studied. The results show that the values of permeability kC after clogging and permeability after cleaning kR decrease rapidly and then gradually stabilize as the number of loadings increases. The anti-clogging performance and recovery effect of permeability of PAC increases with the increase of air void and nominal maximum aggregate size. The residual rate of water permeability of PAC specimens with different air void was significantly different, and the γ value of PAC specimens with larger air void was larger under the same cycle number. The cleaning effect was ranked as high-pressure water washing > vacuum pumping> manual brushing. Particles with the size range of 0.15-2.36 mm are the key particle sizes that cause the clogging of PAC-13 specimen, the particle size of PAC-13 clogging sensitive particle gradually increases with the increase of air void. © 2020, Materials Review Magazine. All right reserved.