Exploring Mixed-Use Measurement And Characteristics On The Block Level Of The Old City And Hexi New Town In Nanjing

Mixed use is of vital significance in contemporary urban design and research,the measurement of which in the built environment serves as the groundwork in this field.However,the basis of mixed-use measurement in China is still relatively backward,and the research on theory and technical methods needs to be further promoted.On the basis of combing the related concepts and measurement methods of mixed use,the paper examines the POI data-based method of Mixed-use Index(MXI)on the level of blocks and the GIS platform-based approach of mixeduse mapping,which focuses on measuring and expressing the mixed-use degree itself intuitively.Taking the old city and Hexi New Town in Nanjing as examples,it further analyzes and interprets the statistical characteristics and spatial distribution characteristics of mixed use in the old and new city blocks,so as to understand and master the external constraint mechanism and actual operation mode of mixed use.The primary conclusion is that the old city of Nanjing is dominated by block units with medium and high mixed-use degree,and the spatial distribution of mixed use is in a circle relationship: the mixed-use degree of the middle area is the highest,the outer edge area is the second,and the central area is the lowest,while Hexi New Town is dominated by block units with dual functions and medium mixed-use degree,and the spatial distribution of mixed use shows a multi-center series relationship: the mixeduse degree of the three core areas is generally the highest,the area along the development axis of Jiangdong Road is the second,and the urban edge area is the lowest.In addition,there is also a certain common law about the distribution of mixed use in the old and new city blocks,that is,it has a certain correlation with the distribution of urban public transport stations,especially high-mixed block units.The research results in this paper can basically indicate the mixed-use characteristics of the old and new city blocks in Nanjing and that the above-mentioned methods can thus be applied to get an overall picture and analysis of mixed-use degree in urban built-up areas.The design experiment takes Wanda block,a high-mixed block with poor spatial quality in Hexi New Town,as the object.Based on the analysis about the material form law of good spatial quality in relevant high-mixed block cases,the connectivity,accessibility and comfort of roads and the publicity of blocks in Wanda block are improved by means of structure adjustment,function layout optimization and public interface form transformation,so as to change the current situation of “urban island”,make it fully integrate into the overall urban environment and stimulate more urban vitality.The design results provide a feasible data support and design strategies for the high-mixed block unit to further improve its spatial quality and vitality.The text of the paper is about 49,000 words,with 65 figures and 23 tables.Except for the figures and tables indicating the source in the text,other charts are drawn by the author.