Preliminary Research Of Technology Of Rain Garden Under The Guidance Of Sponge City Construction

"Governing water must go ahead of governing nation".Our country is based on agriculture however has experienced water problems for many years,so that this opinion has been a common view.Nomatter the story of "Dayu" or the "Dujiangyan Weir",as well as the Three Gorges Dam Project,have explained the relationship between governing water and nation.How to better manage the water resources problem has plagued mankind all the time,in the 21st century,urban flood has become the biggest threat to human survival.The traditional way of thinking,can not effectively prevent the deterioration of urban water environment,also caused a huge waste of water resources.In ensuring the premise of urban waterlogging drainage safety,to achieve the rainwater in urban area of accumulation,penetration and purification,and to promote the idea of rainwater resources utilization and ecological environmental protection have been put on the agenda of the utilization of urban water resources.Aiming at the situation that the relative concentration of rainfall in our country,the scholars put forward the theory of "Sponge City".Sponge City means that the city can be like a sponge,which has a good "clastic" in the adaptation to the environment and to respond to natural disasters.When it rains,the city can collect water,restore water,filter water and purify water;when it is needed,the city can "release"the rainwater and to use.The first ting of construction of Sponge City is to reverse the concept.Traditional urban construction has rigid pavement everywhere.When it rains heavily,city mainly relies on the sewers,pumping stations and other "grey" facilities to drainage.Using the quickly drainage "and"terminal focus "as the main planning and design philosophy of control.often causes floods and droughts.According to the Sponge City construction technology guide ",the future urban construction will emphasize using grassed swales,rain garden,sunken green spaces and other" green "measures to organize,drainage,and to use " slow row released and distributed source "as the main planning and design philosophy of control.Rainwater garden is an ideal method to realize the construction of sponge city.It is a kind of rain flood control technology,which is a collection of rain flood storage,purification and infiltration function.The rain garden is the natural or artificial construction of low-lying land with reasonable retention or planting arbor and shrub and groundcover plants,in order to achieve the rainwater storage function and flood control.The purpose of this paper is to discuss the feasibility of constructing a sponge city rain flood control network through the theory and case study of the rain garden.In this paper,the relationship between the city and the rain garden,the characteristics and the value of the rain garden,the technology and the design method of the sponge city were studied,and some results were obtained by using the literature research,case study and comparative analysis:(1)The fit degree of the technology of the rain garden and the sponge city is discussed from different views.(2)Analysis of the advantages and values of the rain garden as the urban rain flood management technology.(3)Comb and sum up the different types of rain garden.(4)Explore the construction of the rain garden in the sponge city construction process and the general design principles.To built the Sponge City needs sponge.Constantly improving the scale and quality of the "sponge"is a kind of important means to build a sponge city.As an efficient and convenient technique,the rainwater garden provides a possibility for the composition of the sponge city.This paper puts forward the "variability" of the rain garden.This feature makes the rain garden to adapt to different site conditions,play different functions,and show different effects of different landscape landscape through appropriate changes of their own form and structure.The research work of this paper has certain practical significance.Through the collection and collation of the results of previous studies,and the research of the domestic and foreign examples,this paper analyzed and summarized the different forms,functions and construction scale of the rainwater garden.Based on this theory,this paper classifies the technical system of the rain garden from many angles,and hopes to provide a theoretical reference for the construction of the sponge city.