The Research On The Evolutionand Optimization Of CBD Public Space With City-industry Integration Development

In recent years,with the changes of city location,industrial structure and space requirement,more and more city planners have put forward the concept of city-industry integration.As the inevitable result of the city integration development and multi-functional development,city-industry integration became the mainstream theory of city planning.Central Business District(CBD),as the urban center of the third industry,was the core business district,which traditionally had the core functions of financial,trade,services and exhibitions.With the influence of the idea of city-industry integration,more and more CBDs get rid of the role of the pure business district,showing the characteristics of the cities scientific,technological,cultural and activity core.This research is about the public spaces in CBD with city-industry integration.This paper mainly consists of three parts: the evolution of CBD function,the characteristics of public space activities in CBD,the evolution of CBD public space system.The research on the functional evolution of CBD is mainly about the mixed-use in the CBD core area and the expansion of the CBD edge area.The study about the mixed-use in the CBD core area focused on the land use and the transformation of building function in CBD area and quantitatively analyzed in three contexts: land usage,business development intensity,and vertical mixed-use development.The paper summarized that there were three typical characteristic of city-industry integration of CBD: more mix land usage,lower business development intensity and the tendency of non-business development of the ground floor.The study about the expansion of the CBD edge area analyzed three expansion ways: explosive expansion,enclave expansion,spreading expansion.And spreading development was the common and rational expansion way of the CBD edge area.Changes in function affected the public activities.Based on the investigations,the research on the characteristics of public space activities in CBD is mainly about the population structure,the type of public activities and the demand for public activities.The paper analyzed the difference of activity types between city public space and CBD public space.Through the field observation about the use of public space,the paper discussed the characteristics of usage with different groups of people,such as white-collar workers,residents and visitors: 1,the primary demand of the white-collar public activities was walking distance;2,the primary demand of the residents and visitors public activities was accessibility.The research on the evolution of CBD public space system was based on the comparative study about the Bund CBD,Hong Qiao CBD,Lujiazui CBD and Beijing CBD.The study analyzed the development trend of the outer space in CBD,the change of the public space walking coverage,the quantitative character of public space and the development of the layout.The evolution law of the public space system in the city-industry development of CBD was summarized.The study further analyzed the public gallery space that showed the development features of “from nothing to gradually building the corridor network system”,the city square that showed the development features of “from the profile surface into the block”,and the urban green public space that showed the development features of “from centralized to decentralized”.In the end,the optimization suggestions to design the better space were put forward.