Spatial Morphology Lab 01. International laboratory for comparative research in urban form. Street networks, Sweden - Motorised network of Stockholm

GIS-datasets for the Street networks of Stockholm, Gothenburg and Eskilstuna produced as part of the Spatial Morphology Lab (SMoL). The goal of the SMoL project is to develop a strong theory and methodology for urban planning & design research with an analytical approach. Three frequently recurring variables of spatial urban form are studied that together quite well capture and describe the central characteristics and qualities of the built environment: density, diversity and proximity. The first measure describes how intensive a place can be used depending on how much built up area is found there. The second measure captures how differentiated the use of a place can be depending on the division in smaller units such as plots. The third measure describes how accessible a place is depending on how it relates with other places. Empirical studies have shown strong links between these metrics and people's use of cities such as pedestrian movement patterns. To support this goal, a central objective of the project is the establishment of an international platform of GIS data models for comparative studies in spatial urban form comprising three European capitals: London in the UK, Amsterdam in the Netherlands and Stockholm in Sweden, as well as two additional Swedish cities of smaller size than Stockholm: Gothenburg and Eskilstuna. The result of the project is a GIS database for the five cities covering the three basic layers of urban form: street network (motorised and non-motorised), buildings and plots systems. The data is shared via SND to create a research infrastructure that is open to new study initiatives. The datasets for Amsterdam will also be uploaded to SND. The datasets of London cannot be uploaded because of licensing restrictions. The street network GIS-maps include motorised and non-motorised networks. The motorised networks exclude all streets that are pedestrian-only and were cars are excluded. The network layers are based on the Swedish national road database, NVDB (Nationell Vägdatabas), downloaded from Trafikverket (https://lastkajen.trafikverket.se, date of download 15-5-2016, last update 8-11-2015). The original road-centre-line maps of all cities were edited based on the same basic representational principles and were converted into line-segment maps, using the following software: FME, Mapinfo professional and PST (Place Syntax Tool). The coordinate system is SWEREF99TM. The map covers all Stockhom region (Stockholm Län). In the final line-segment maps (GIS-layers) all roads are represented with one line irrespectively of the number of lanes, except from Motorways and Highways which are represented with two lines, one for each direction, again irrespectively of the number of lanes. We followed the same editing and generalizing procedure for all maps aiming to remove errors and to increase comparability between networks. This process included removing duplicate and isolated lines, snapping and generalizing. The snapping threshold used was 2m (end points closer than 2m were snapped together). The generalizing threshold used was 1m (successive line segments with angular deviation less than 1m were merged into one). In the final editing step, all road polylines were segmented to their constituting line-segments. The aim was to create appropriate line-segment maps to be analysed using Angular Segment Analysis, a network centrality analysis method introduced in Space Syntax. All network layers are complemented with an “Unlink points” layer; a GIS point layer with the locations of all non-level intersections, such as overpasses and underpasses, bridges, tunnels, flyovers and the like. The Unlink point layer is necessary to conduct network analysis that takes into account the non-planarity of the street network, using such software as PST (Place Syntax Tool).本数据集为空间形态实验室（Spatial Morphology Lab, SMoL）项目产出的斯德哥尔摩、哥德堡及埃斯基尔斯蒂纳街道网络地理信息系统（Geographic Information System, GIS）数据集。 SMoL项目的核心目标是通过分析范式，构建用于城市规划与设计研究的严谨理论与方法体系。研究聚焦于空间城市形态中三大高频变量，三者可较为全面地刻画建成环境的核心特征与属性：密度、多样性与邻近性。 第一项指标衡量地块的开发强度，其依据为区域内建成用地占比；第二项指标反映地块利用的分化程度，该分化由地块等更小单元的划分所决定；第三项指标表征地块的可达性水平，其取决于该地块与其他地块的空间关联关系。实证研究表明，上述三类指标与城市人群活动（如步行出行模式）存在显著关联。 为支撑上述目标，本项目的核心任务之一是搭建面向空间城市形态比较研究的GIS数据模型国际平台，研究对象涵盖三座欧洲首都：英国伦敦、荷兰阿姆斯特丹与瑞典斯德哥尔摩，以及两座规模小于斯德哥尔摩的瑞典城市：哥德堡与埃斯基尔斯蒂纳。 本项目最终产出覆盖上述五座城市的GIS数据库，包含城市形态的三大基础图层：街道网络（机动与非机动）、建筑与地块系统。 本数据集通过SND平台共享，以构建开放接纳各类新研究项目的科研基础设施。阿姆斯特丹的数据集也将上传至SND平台，而伦敦的数据集因授权限制无法对外共享。 本街道网络GIS地图包含机动与非机动两类路网。机动路网排除所有仅允许行人通行、禁止机动车驶入的道路。路网图层基于瑞典国家道路数据库NVDB（Nationell Vägdatabas）构建，数据从瑞典交通管理局Trafikverket下载（下载链接：https://lastkajen.trafikverket.se，下载日期：2016年5月15日，最后更新日期：2015年11月8日）。所有城市的原始道路中心线地图均遵循统一的基础表达规范进行编辑，并通过FME、MapInfo Professional及PST（Place Syntax Tool）三款软件转换为线段地图。数据集采用的坐标系为SWEREF99TM，覆盖范围为整个斯德哥尔摩地区（Stockholm Län）。 在最终的线段地图（GIS图层）中，除高速公路与快速路外，所有道路均以单条线段表示，与车道数量无关；高速公路与快速路则以双向各一条线段的形式呈现，同样不考虑车道数量。所有地图均采用统一的编辑与概化流程，以消除数据误差并提升不同路网间的可比性。该流程包括删除重复与孤立线段、节点匹配及数据概化。本次采用的节点匹配阈值为2米（间距小于2米的端点将被合并），数据概化阈值为1米（角度偏差小于1米的连续线段将被合并为单一线段）。在最终编辑步骤中，所有道路多段线均被拆分为其组成的单一线段，目的是生成适配角度线段分析（Angular Segment Analysis）的线段地图——该方法是空间句法（Space Syntax）提出的一种网络中心性分析手段。 所有路网图层均配套“非连接点（Unlink points）”图层：该GIS点图层标注了所有非平面交叉口的位置，包括立交桥、地下通道、桥梁、隧道、高架路等。该非连接点图层是利用PST（Place Syntax Tool）等软件开展考虑街道网络非平面特性的网络分析的必要前提。