The Research Abou The Construction Of Modern Chengdu Sponge Citye Based On Ancient Rainstorm Preventing And Utilizing System

The rapid urbanization rate in recent years has been accompanied by a series of urban water environment problems,including urban waterlogging,drought,drawdown and ground subsidence.,Since President Xi Jinping put forward the construction of sponge city in 2013,it has become a research hotspot.However,the present situation of sponge city construction is not optimistic,so further research is needed.In the long struggle against drought and flood,the ancients accumulated a great deal of valuable experience which can be used for reference in modern sponge city construction.There are a number of studies on the management measures and facilities of sustainable rain flood in ancient cities.However,research on the inductive system of the ancient rainstorm control and utilization measures is still lacking.This paper is based on the ancient city,focuses on the ancient cities,establishes the ancient rain flood prevention and utilization system and its general rule,takes ancient Chengdu as the case,studies the evolution process and status quo of this system to put forward the design strategy of the of modern Chengdu Sponge City construction based on the ancient system.The main research work and conclusions can be summarized as follows:(1)Through literature research,the ancient rainstorm preventing and utilizing system has been established by 5 aspects as watershed improvement,settlement site selection,urban water adaptation planning,engineering measures and the theory,law and ideology about rainstorm management.The using of sustainable local materials in line with local conditions lead to a harmonious relationship between human and water on the condition of limited technical terms.Actively learning from its experience,protecting and exploiting the heritage is beneficial to the construction of modern sponge city and reduce drought and drought,and vice versa,the opposite can lead to serious consequences.(2)Taking Chengdu as the case,analyzed the evolution process and status quo of ancient rainstorm preventing and utilizing system by literature research and field investigation,focusing on the evolution of urban hydrological structure.On the one hand,the ecological values of ancient Chengdu in the development process and the harmonious water environment which has been lasted for thousands of years is positive.On the other hand,it is also a pity that this system has damaged a lot in the modern city construction.(3)Selected WP,RD,RF and CR as the evaluation indexes of urban urban hydrological structure of Chengdu and came to a conclusion that the speed and degree of damage is serious.The rules can be summarized as follows:(1)Difference in grades,the lower level of the branch has,the more serious the damage is;(2)Difference in space,the closer to the city center,the hydrological structure index is lower,the closer to the city periphery,the decline of the index is greater.(4)Relying on green space planning and rebuilt difficulties,the paper put forward the design strategy of the of modern Chengdu Sponge City construction based on the ancient system by 3 levels as macroscopic,mesoscopic and microscopic levels,and 3 degrees as status quo protection and original restoreration,texture reservation and culture reservation.