Research On The Relationship Between The Form Characteristics Of Street Blocks And Function Of Urban Policy In China

Urban block is an important part of urban physical form,and it is a land unit which is surrounded by urban roads,including plots,buildings,green sites and square space,facilities and other elements,and the combination of these elements have form block attribute characteristics,such as traffic environment around the surrounding road,block scale,land use,plots division number,plot ownership boundary,plot shape,buildings distance,open space scale,building wide along street,building height,street wide,and so on.Urban block form might be described as the result of numerous shaping processes in varying social layers at a given place through time,and it is comprehensive influenced by the elements of social,economic,political,historical,environmental and so on,especially from the power of internal and external economic development and urban coding control,and it mainly shows for three forms of the urban block plane shape and group combination form of buildings and block interface form.During the formation and evolution of urban block form,the effect of economic power and social behavior and history and geography and culture is spontaneous,not transferred by people's will,but regulatory guidance can directly manipulate the construction of city,which has very deep association influence during the development of urban blocks form.The main relationship point between urban form and relevant urban regulations is the "change of block attribute characteristics",while the relevant rules and technical regulations and standards of city planning and construction are solving the city function problems of ventilation and lighting and fire earthquake and traffic congestion by controlling the intensity of land development and buildings construction position,which are destroying the adaptive relationship between function and form,so cause the morphological change,which relatedly affects the plane texture,spatial contour,building group space organization order of urban block form and affects the quality of urban environment.Since 1980s,with the rapid development of economy and urbanization,the very quite urgent problem of mankind facing is the lack of characteristic and intensive and livable urban environment,some urban form problems are discussed about city congestion and lack of public space and isolation of population and land function and modern suburbs spreading repeatedly,so urban design is very important for creating urban environment based on human,how to make urban design return to its root,how to control urban space form for improving the urban environment quality becomes a study problem for experts.Some debate research from traditional zoning to the development based on form think that the question is mainly attributed to the main planning of functional separation and car traffic and the traditional zoning by using rigidly,which think that the way of solving these problems may be the planning and urban design methods through the establishment of design rules based on form to remedy or prevent the city environment problem,and may provide design tools through the regulations controlling for balancing the relationship between diversity and order in the city.In the process of global urbanism,in order to prevent be out of control of city development and construction,China also face a serious problems of how to effectively manage and control urban form.China is facing a large number of demands of urban renewal and urban spatial quality optimization,urban design plays an important role in the level of fine control of space form.Through controlling urban block form features for reshaping urban spatial morphology characteristics and enhancing the quality of space environment,which is directly related to the direct experience of people for the city view and comfort and urban activities.At present,our country lacks the special regulation documents and regulations to control the urban material form,it mainly relies on the urban design guidelines to make plans for the urban blocks and plots and buildings,and for the requirements for the building form of the blocks.The urban design guidelines include land fragmentation,plot index,building distancre,architectural concession,building height,building interface control line and building sticker rate to control form features of block plan,plots and buildings and block interface,but because china urban block attribute characteristic is very complex,which corresponds to the form diversity of the urban block plan and plots and buildings and interface,and because urban design guidelines are at the stage of exploration or trial,and the relevant laws and regulations have not been fully established and implemented,and because the direct or indirect regulations control function of the national,provincial and local city on the characteristics of urban block is not clear,and because urban design index cannot join with the provisions of relevant regulations,and so on,the index is difficult to implement in many practical situation.Case as Nanjing city,While Nanjing construction mainly solve the city function problems through controlling land development intensity and buildings position and so on,with the control detailed planning as means,on the basis of control of relevant laws and regulations of country and local city,which has brought the environment quality problems of urban form runaway of urban block land chaos and street space scale extensive and plots division larger and street interface disorder and buildings order messy and so on,so it becomes one of the most mainly city problems of need solving that how to effectively control city development and construction and shape the urban form adapting the actual Chinese situation for improving urban environment quality,and urban design guideline has not been put into legal documents,urban design index cannot join with the provisions of relevant regulations,which causes the related indexes can not be realized in many cases.So,focusing on urban policy in China,case as Nanjing city,the study scope is mainly limited to the old urban area of Nanjing,which is closely related to urban regulation and control,from the three scales of the block plan,plots and buildings assemblage,and the street architecture interface,on the basis of summarizing the related research theories and methods,and identifying the attributes characteristics of urban block,and combing the main provisions of relevant laws and regulations of national,provincial and local cities,this paper is set a study path in general,which is two aspects study,from the historical reduction the role of regulations in the form of construction to the data generation and quantitative analysis of correlation between index and block form.The first is through a lot of observation and analysis to the block completed morphology,through the method of case age section selection,select the block samples,corresponding provisions associated with main indexes of block attributes,using the method of historical situation,reproduce the role of regulations control to the morphology in the historical context.The second aspect is relevance analysis of the theoretical and empirical between the main index of control function and block form feature,corresponding to three levels of scale of block plane,plot and buildings,and block interface,on the base of theoretical analysis through creating regulations theory model and correlation evaluation chart using comparative analysis methods of historical design deduction and graphic superpositior and data curve,the study analyzes the relevance between relevant urban regulations and block form features from theory and practice aspects.This study has mainly obtained three aspects of results:theoretical value,research methoc innovation,relevance effect,and provides a theoretical basis and framework.The research has great theoretical and practical significance,which provides a scientific method for the regulation of urban design guidelines,the operability of specific urban design control,the renewal of urban design and the promotion of space quality.It has great theoretical contribution to know the complex city,to renew the concept of management and control,to advocate the sustainable development of urban construction,to perfect the relevant regulations and to revise the city design norms on the basis of the morphological perspective.