The Research On Rainwater Harvesting Green Space Design In Semi-humid Region

With the process of urbanization in China,the increasing utilization rate of impermeable urban underlying surface caused a series of serious problems such as frequent urban waterlogging,serious water pollution,water shortage.In semi-humid region,due to the climate condition,large amount of concentrated rainfall and clearly defined wet and dry seasons,pushed the urban storm problem to a higher level and has seriously threatened people's life and property.Most of existing traditional public infrastructures have fallen behind city development and have the shortcomings including unitary function,ecological detraction,poor aesthetic benefits etc.It needs to be changed that urban stormwater management only relys on grey infrastructure.This dissertation proposed the concept of rainwater harvesting green space design,aims to explore the roles of green space in urban stormwater management from a perspective of landscape architecture,to develop a new urban stormwater management system based on both green and grey infrastructures.It has positive meaning for sustainable urban developmentThis dissertation summarizes the related research progress and case study in China and abroad,analyzes the stormwater management frameworks and green space design such as the Best Management Practices(BMP),Low Impact Development(LID),Water Sensitive Urban Design(WSUD),Sustainable Urban Drainage System(SUD),sustainable urban water resources system and five theories of Sponge City,in order to summarize experience and rethink current research on rainwater harvesting green space.This dissertation points out that the basic reason for the research lack of systematic in China is the shortage of rainwater harvesting green space design framework as a guideline.though document study,combing the development process and understanding the nature of design research,this dissertation defines the concept and significance of design research,explain the design epistemology and design practical theory,establishes the framework of design research,combining with the characteristics of rainwater harvesting green space design,build the research framework which is suitable for its own characteristics.Based on the research framework,this dissertation,firstly,according to the green space basic function and the requirements of stormwater management,a series of rainwater harvesting green space design problems are constructed and the detailed target of rainwater flood control in green space are set based on the characteristics of hydrology,meteorology in semi-humid region.Secondly summarize the knowledge of rainwater harvesting green space design,including the basic design principles,the selection and implementation of technical facilities and related design strategies,the combination of basic function and technical facilities in green space,five aspects of stormwater detention and retention capacity.Then,SUSTAIN and SWMM rainwater management models are used to assist the initial scheme generation of rainwater harvesting green space,the cost-based scheme optimization and the simulation of the scheme performance.And constructs the scheme evaluation system of rainwater harvesting green spaces according to design problem framework,and evaluates the scheme by using the quantitative data obtained from simulation.Finally,corrects the design experience used in progress,and sums up the new generated design knowledge to complete the entire design research.Besides,Qian' an Binhu East Road Park and Jinzhong Shehuo Park,as examples in this dissertation,explained the whole process of rainwater harvesting design methods.By the study of rainwater harvesting green space design in semi-humid region,this dissertation provides a new approach to introduce the green space into urban stormwater management.-in the premise of ensuring the basic functions of green space,implement the monitoring of runoff volume,peak flow,runoff pollution,water resource utilization and aims to expand the design concept and emphasis more on runoff control,rain water quality and ease the water resource problems for city.