Research On Functional Density And Functional Diversity Of Hefei Old City Blocks

As the root of the city,the old city occupies an important position in the urban renewal and development.With the development of the city,the development of the old city also faces a series of new problems.At present,due to the blind renovation and development of the old city,the results presented by the old city have not met expectations.There have been various problems such as the appearance of the old city,the declining environmental quality of the blocks,and the rapid decline of the vitality of some cities.At present,the old city of Hefei is facing the problem of urban functions that can overlap each other in a limited space.The old functions do not go away,the new functions are constantly filled,and the space development is unbalanced.Urban function problems such as unbalanced space development have brought a heavy burden to the further development of the old city The pressure must clearly sort out the functional density and diversity of Hefei's old city blocks,and scientifically diagnose the problems in the old city,so that it can be targeted in the development and construction of the old city in the future.Nowadays,China has entered the era of big data,and the generation of large amounts of urban data provides the possibility of using data to carry out scientific and accurate research and analysis of urban problems.Therefore,the use of big data to efficiently sort out the research on functional density and diversity has become the focus of research on the old city of Hefei at this stage.This paper takes the old city block of Hefei as the research basis,and expounds that the function density and diversity of the block are closely related to the urban vitality of the old city.Taking into account further that it is necessary to study the constituent elements of the block space for the block research,therefore,the spatial constituent elements of the old city block in Hefei are analyzed.First of all,in the relevant theoretical research,the relevant studies on the spatial form,functional density and diversity of the blocks were sorted out;further,through the data of the blocks within the old city of Hefei,building outline data of the old city,real-time traffic accessibility data and The POI data of historical cultural facilities in Hefei analyzed the spatial form of the old city blocks,the accessibility of all blocks in the old city area,and the historical and cultural values.Then,using the POI data in the old city area,the functional density and Diversity was analyzed.On this basis,the Shannon Diversity Index and spatial autocorrelation analysis method were used for in-depth calculations,and the calculation results were visually expressed.Finally,in order to gain a deeper understanding of the factors that affect the functional density and diversity of the neighborhood Forming mechanism,according to the correlation analysis of the spatial form and accessibility of the block with historical and cultural values as the influencing factors.The areas with higher density of functional facilities within the old city block of Hefei City are more distributed inside the old city,the blocks near Huaihe Road Pedestrian Street,the blocks along both sides of Yangtze River Middle Road,etc.The blocks on the outer side of the old city are Anliang Dongyi Square Blocks,blocks where the city government dormitory is located,etc.,but on the whole,the most densely distributed blocks along both sides of the Yangtze River Middle Road have the most distribution,and the overall functional facility density is positively correlated in spatial distribution,that is,high functional density blocks and other high functional density blocks It has the characteristics of mutual aggregation in space;the number of functional types of most blocks is distributed between 8-13 types,the diversity index of each block is relatively close to the average,and the overall diversity of block functions is not too high.Continue to enrich the space,the hotspots with high functional diversity are mainly distributed in the central area of the old city,around the municipal square;from the plane scale of the block,the overall block of the old city of Hefei is generally small,and the area is more suitable.The proportion is the least,the number of blocks on the short side is not suitable for the area,and the short side is not suitable for the area.In terms of the shape of the block,there are the most rectangular blocks.From the block layout,the old city block has a total of 3 middle block layouts,which are divided into regular layout,enclosed layout and free layout;from the perspective of the coverage of block buildings,Hefei The overall building coverage rate of the old city of the city is low,and the combination of buildings is divided into four types: point type,row type,enclosed type,and mixed type;from the perspective of the three-dimensional shape of the block,the average height of the building in the old city block overall shows that the peripheral block is low In the state of high internal blocks,the blocks with high buildings on the whole block are distributed on both sides of the Middle Yangtze Road.The overall height of the old city is appropriate.The block rate along the two sides of the Yangtze Road is increased and the development intensity is greater;The blocks are distributed outside the old city;in the study of the formation mechanism of functional density,the variables of block building coverage,block average height,block volume ratio,public transportation accessibility and cultural score are positively correlated,among which block building coverage is The block volume ratio has the greatest impact on the functional density;in the study of the formation mechanism of functional diversity,it is related to the block area and block Long and short sides,block building coverage,block building average height,block floor area ratio,public transportation accessibility and cultural scores are positively correlated,but each related variable does not show a strong correlation with its functional diversity.Overall,the use of big data to study the functional density and diversity of Hefei 's old city blocks can reflect the current situation objectively,and it can be used for reference for further research in Hefei's old city.