Study On The Scheme Of Spongification And Reconstruction Of Built Urban Roads

Under the problems caused by rapid urbanization and traditional road drainage,the urban traffic environment has been seriously affected.Therefore,we should not only pay attention to the design of road structure,but also pay attention to the design of road drainage and greening ancillary facilities.The purpose of this paper is to study the transformation of urban roads by using the concept of sponge city construction,and to put forward the transformation scheme suitable for each component object of urban roads,so as to alleviate the contradiction between frequent flood and waterlogging disasters and relative shortage of water resources faced by cities in our country.Firstly,this paper analyzes the research status at home and abroad.Based on the concept of "seepage,stagnation,storage,net,use and arrangement" in sponge cities,this paper analyzes on the nine low impact development facilities suitable for urban roads,and sums up the calculation methods and comparison and selection principles of different functional facilities.Then,taking the components of the urban road as the transformation object,the concrete transformation schemes are put forward,which are as follows: the driveway,the sidewalk and the parking lot of the road adopt different types of permeable paving according to the actual road conditions,so as to improve the infiltration capacity of Rain Water.To realize Rain Water’s on-the-spot absorption;The green belt adopts the sinking design,flexibly selects the biological detention facility,the planting grass ditch,the ecological tree pond and so on many kinds of facilities combination form,realizes the Rain Water transfer,the purification and the infiltration;The road edge stone adopts the opening,drilling or spacer type to enhance the drainage effect to the pavement Rain Water;Rain Water mouth adopts the environmental protection type rain nozzle,which effectively reduces the pollution of the receiving water body by Rain Water in the initial stage.At the intersection of viaduct and overpass with ordinary pavement,Rain Water tank,water storage module and ecological facilities were used to store and collect Rain Water.Taking three typical roads as examples,according to the cross section form and slope direction of the road,a reasonable transformation scheme is designed.The road system is realized by using the cross section diagram,the plane diagram and the flow chart of Rain Water discharge step to show the infiltration,stagnation,storage,net and use of Rain Water.The process of arrangement.Finally,the field investigation and case study of Qinhuang Avenue Reconstruction Project in Xixian New area are carried out.In order to solve the problem of poor geological and soil permeability of collapsible loess,the solutions of L-shaped reinforced concrete retaining wall and replacement of biological retention medium are put forward in order to solve the problem of poor geological and soil permeability of collapsible loess.Through the design of road LID facilities and the calculation and comparison of actual control and storage volume,the calculation and comparison of rainfall comprehensive runoff coefficient and the monitoring and calculation of pollutant concentration before and after the revamping are carried out.The results show that the total amount of runoff has been realized after the project transformation.The goal of controlling the total amount of runoff pollution is that the phenomenon of road water accumulation has been obviously improved.