Study On The Effects Of Sodium Polyacrylate On The Properties Of Pervious Concrete

With the widespread implementation of water-permeable materials,water-permeable concrete has received extensive attention from researchers at home and abroad because of its strength and water permeability.However,due to its rapid water penetration,it cannot retain enough water,and it cannot effectively cope with the long-term evaporation of the road surface to reduce the air temperature.There are still certain limitations to the improvement of the urban heat island effect.As a new type of super absorbent resin,sodium polyacrylate(PAAS)can absorb hundreds of times its own weight of water.Because of its unique water retention properties,it is widely used.Not only that,but also because of its unique spatial network structure.It also has special functions such as good swelling,thickening,and adhesion.It can be used as a water-retaining material to effectively store a certain amount of water and absorb the heat generated by the city;alleviating the heat island effect is the best way to realize the combination of artificial "sponge" and natural "sponge",so that the road surface has "rainy season water absorption,dry season "Release water" function.This paper organically combines water-permeable concrete with internal curing.It mainly introduces the research status of water-absorbing concrete with high water-absorbent resin at home and abroad.It systematically analyzes the related properties of water-permeable concrete with high water-absorbent resin and analyzes the existing problems and future developments of internal curing materials thus to expand its application in the field of permeable concrete.In order to explore the influence of superabsorbent resin on the permeability of pervious concrete,this experiment uses three different factors.PAAS content,water-cement ratio,particle sizes of coarse aggregates to design orthogonal test,while the average range method and the analysis of variance method were used to systematically study the physical and mechanical properties of various factors and levels on the permeability coefficient,water retention rate,7d/28 d compressive strength,28 d flexural strength of permeable concrete,as well as resistance to sulfate corrosion.The results show that in terms of physical properties,the primary and secondary factors affecting the permeability coefficient of permeable concrete are particle sizes of coarse aggregates > water-cement ratio> PAAS content;coarse aggregate particle size is a significant factor for the permeability coefficient of permeable concrete;when the water-cement ratio is0.35 and when the aggregate particle size is 15-20 mm,the water permeability coefficient can reach 28.12mm/s.The primary and secondary factors affecting water retention rate are: PAAS content> water-cement ratio> coarse aggregate particle size.The PAAS content is a most significant factor for the water retention of permeable concrete;when the water-cement ratio is 0.3 and the PAAS content is 0.4%,the water retention can reach 92.43%.In terms of mechanical properties,the main and secondary factors affecting the compressive strength at 7d/28 d are PAAS content> water-cement ratio> coarse aggregateparticle size.The PAAS content is a significant factor for both 7d and 28 d compressive strength of permeable concrete.When the water-cement ratio is 0.30,the PAAS content is0.2%,the 28 d compressive strength can reach 13.44 MPa.The primary and secondary factors affecting the 28 d flexural strength are PAAS content> water-cement ratio > coarse aggregate particle size.The PAAS content is a significant factor for the 28 d flexural strength of permeable concrete.When the water-cement ratio is 0.30,the PAAS content is 0.2%,the 28 d flexural strength can reach 2.94 MPa.About durability the primary and secondary factors affecting the resistance to sulfate corrosion are water-cement ratio > PAAS content > coarse aggregate particle size.The ratio of water-cement ratio and PAAS content are relatively significant factors to the sulfate resistance coefficients of the permeable concrete;when the water-cement ratio is 0.30,the PAAS content is 0.2%,the corrosion resistance coefficient can reach 0.893.