Study On Performance And Application Of Pavement Material In Sponge City Construction

The demand for urban roads is not only to travel safely,but also pay attention to the ecological nature of urban roads.As an important part of the construction of sponge city,OGFC pavement,which plays an important role in the reduction and purification of groundwater,has attracted concerned study.From the perspective of permeability properties,mechanical characteristics and water purification performance of OGFC pavement,the performance of two kinds of modified OGFC asphalt mixtures(High Viscosity Additive and Thermo Plastic Styrene,abbreviated as HVA and TPS)with the variation of void fraction was studied,the design and construction technology of OGFC asphalt mixture was summarized.It may provide reference for the engineering application of sponge city construction.The main research contents and results are as follows:1.Experimental tests on the relationships among permeability coefficient,permeability coefficient and porosity were conducted,and mathematical functions to describe the relationship among the indexes were established.Experimental results showed that,permeability performance between the two modified asphalt mixtures was similar under the same porosity condition.2.Water purification performance of OGFC pavement was studied.The results showed that,with the increase of porosity,the Suspended Solids(SS)and Chemical Oxygen Demand(COD)purification performance of OGFC asphalt mixture increases.Comparing the influence of two modifiers on the purification effect of OGFC,it showed that if void ratio less than 20%,the type of modifier had little effect on the purification effect of OGFC.When void ratio more than 20%,the SS and COD purification effect of HVA modified asphalt mixture was superior to TPS modified asphalt mixture.3.the mechanical performance of two kinds of asphalt mixture was studied.The results showed that the dynamic stability of OGFC mixture increased firstly and then decreases with the increase of void ratio from 16.8% to 23.2%.With the increase of porosity,the flexural tensile strength,flexural tensile strain and dynamic modulus all decreased.Besides,the road mechanical of HVA modified asphalt mixture was better than that of TPS modified asphalt mixture.4.Combined with engineering application of sponge city construction,mix proportion design and construction technology of OGFC mixture in municipal road was studied.Due to it's good permeability,road performance and rainwater purification function,OGFC pavement may play an important role in the construction of sponge city.