Study On Physical Mechanics And Anti-erosion Performance Of Hybrid Fiber Permeable Concrete

Permeable concrete has low strength due to its own structure and cannot be widely used in urban construction.There have been a large number of research applications on improving the physical and mechanical properties of concrete with fiber in a reasonable amount.In this paper,polypropylene(PPF)and basalt fiber(BF)are mixed into permeable concrete to improve the physical mechanics and corrosion resistance of permeable concrete.The main research contents are as follows:(1)Based on the volume method mix ratio design,the selected 4 sets of water-cement ratios(0.25,0.26,0.27,0.28)and 3 sets of target porosity(15%,17%,20%)are selected to calculate 12 standard mixes The ratio is prepared by the preparation and molding process of permeable concrete,and the compressive strength of the test piece is taken as the reference to determine the optimal benchmark mix ratio in this experiment.(2)Based on the above-mentioned reference mix ratio,design three kinds of fiber content(0.06%,0.12%,0.18%),and the volume ratio of PPF to BF is 0:1,2:1,1:1,1:2,and 1 :0,a total of five mixed forms are mixed with permeable concrete,and its physical and mechanical properties and corrosion resistance are studied in depth.The main research conclusions are as follows:(1)The incorporation of fiber will reduce the effective porosity and water permeability of the test piece,and the water permeability of the fiber will gradually decrease with the increase in the amount of fiber,but the overall decrease is not large.In this experiment,the test pieces of each test group reach requirements.(2)After the fiber is mixed,the early compressive strength of the specimen will be greatly improved.As the age of the specimens grows,the lifting effect produced by the fiber gradually weakens.Among them,the 1:2 hybrid series,with a fiber content of 0.06%,can improve the compressive strength of the permeable concrete at each age.Fiber has a significant effect on the flexural strength and splitting tensile strength of permeable concrete.Among them,the 1:2 hybrid series has the greatest effect on the 28 d flexural and splitting tensile strength when the content is 0.18%.An increase of 43.96% and 56.30%.(3)After the permeable concrete is corroded,the surface of the test piece and the surrounding edges and corners will fall off.As the number of cycles increases,the greater the damage of the test piece,the incorporation of fibers can reduce the damage process of the permeable concrete.And can effectively reduce the loss of compressive strength of permeable concrete after erosion.The effect of mixing fibers into the matrix in a hybrid manner to improve the permeable concrete is better than that of single mixing.Among them,the 1:2 hybrid series achieves the best when the fiber content is 0.12%.