Influence of Forming Method on Porosity and Frost Resistance of Pervious Concrete
In order to explore the influence of different molding methods on the frost resistance of permeable concrete,the orthogonal test of four factors and three levels was designed by the number of manual insertions,the number of mold loading,the mixing time and the number of solidifications,and the influence law of different molding methods on the porosity of permeable concrete and the change law of the relative dynamic elastic modulus with the number of freeze-thaw cycles were analyzed by using the extreme difference and variance,and the influence order and optimal molding method combination of different molding methods on porosity and frost resistance were obtained.According to the existing freeze-thaw theory,the mathematical relationship between freeze-thaw damage and porosity is established.The results show that the stirring time is the most important factor affecting porosity and frost resistance,and the relative kinetic elastic modulus gradually increases with the increase of the number of freeze-thaw cycles,and the maximum loss of the relative kinetic elastic modulus is up to 75%.The number of freeze-thaws and the amount of freeze-thaw damage show a power function relationship;There is a critical porosity,when the porosity is less than the critical porosity,the porosity and the amount of freeze-thaw damage into a sinusoidal relationship,when greater than the critical porosity,the porosity and the amount of freeze-thaw damage into a linear relationship.
permeable concreteporosityfrost resistanceorthogonal test
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