The four different mixing processes have been ranked in order to determine the effect of processes on the basic properties of pervious concrete modified by nanofibrillated cellulose(CNF).The experimental results indicate that in second-cement-wrapped stone-feeding method,0.018%of CNFs achieve the best pervious concrete effect with compressive strength of 26.79 MPa,the flexural strength of 3.18 MPa,water permeability of 7.33 mm/s,and porosity of 15.95%.0.018%admixture of CNFs can improve the internal pore structure of pervious concrete,without unduly decreasing the permeability coefficient and porosity,and improving the strength of pervious concrete,but when the amount of CNFs exceeds,just the opposite result.The microstructure of pervious concrete shows that CNFs content of 0.018%can improve the connection of interface transition zone and reduce interface pores and cracks,but too much CNFs content leads to the decrease of hydration product compactness,the deterioration of the connection of the interface excess zone,and the deterioration of mechanical properties.
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