Spatial Characteristics,evaluation And Optimization Of Parking Facilities In Large Complex

With the increasing tension of urban land resources and the increasing intensification of land use,it has been an universal development model to build large complexes which combining multiple land demand.The compound travel demand attracted by large complexes brings a lot of parking demand.Thus large accessorial parking facilities have become an important part of urban parking resources.Complex accessorial parking facilities show many different characteristics from traditional parking facilities,as well as bringing new parking problems.There are significant differences in the utilization efficiency of berths in different areas.Some areas are over-saturated and some areas are seriously vacant,resulting in low overall utilization efficiency of parking resources.The complex underground space structure has brought many difficulties to users in finding berths,finding entrances and exits,and finding parking vehicles when they leave,which affecting parking convenience.Therefore,the analysis of the supply characteristics of complex parking facilities and the evaluation of spatial layout are helpful to grasp the macroscopic and microscopic characteristics of such parking lots,and quantitatively analyze the effectiveness of spatial layout,so as to promote the fine development and management of parking resources.Firstly,based on field investigation,this paper summarizes the typical supply facilities of parking facilities in complex construction,and summarizes the classification,characteristics and applicable conditions of various supply facilities.The typical types of complex space form and its influence on parking space and facility layout are further explored.On this basis,the typical combination layout forms of supply facilities are summarized,and the setting conditions and performance characteristics of combination layout are analyzed.Then,based on Arc GIS platform,the data framework,data standards and topological structure for realizing the digitization of the supply data of complex parking facilities are constructed.The whole process method for the collection,storage,management and application of the supply data of such parking facilities is established.On the basis of the data standard,the creation method of three-dimensional visualization model is established.The proprietary visualization analysis tool is designed through the secondary development of Arc GIS.Then,based on the accessibility theory of traffic network,this paper establishes the berth-level spatial layout evaluation index of berths with time as the unified measurement unit of various facilities performance.The expected travel time of motor vehicles reflects the accessibility of berths,and the expected walking time of reflects the convenience of berths.The calculation method of each time component in the parking process is specified,and the calculation method of the contribution weight of multiple paths to the index is defined.The cluster analysis of berths is carried out by Gaussian mixture clustering method,and the berths are divided into high accessibility and low convenience type,low accessibility and high convenience type,All-route balanced type and highest single source convenience type.On the basis of complex network theory,the load evaluation indexes of channel and intersection are established to identify the prone areas of congestion and bottleneck under certain layout.The evaluation index of the entrance and exit is established by calculating the relevant characteristic variables of all berths to the motor vehicle entrance and exit and pedestrian entrance.The difference of the index reflects the homogeneous degree of the spatial distribution of facilities.Finally,taking Ganglong City Commercial Plaza in Suzhou New District as case study,the spatial layout evaluation indexes proposed in this paper are used to evaluate the current layout of various facilities.The existing problems are diagnosed from the indexes results,and the optimization schemes are put forward.The advantages and disadvantages of each scheme are analyzed by index change,which provides quantitative data support for scheme comparison and selection.