Simulation-based route planning for pedestrian evacuation in metro stations: A case study

This paper develops a systematic simulation-based multi-attribute decision approach to route choice planning, in which uncertainties and dynamics underlying pedestrian behaviors during an evacuation are modeled given the complex interaction between pedestrians and the traffic is taken into account. Three factors, namely the length of evacuation route, time of evacuation process and density of pedestrian flow, are identified to have significant impacts on the efficiency of the evacuation process, especially at peak hours in a metro station. Two route planning strategies, as specified in Scenarios I and II, respectively, are proposed to simulate the pedestrian evacuation performance. Four key performance indicators (KPIs), namely average pedestrian density, average evacuation length, average evacuation time and average evacuation capacity, are put forward to assess the evacuation performance within different route planning strategies. The values of these KPIs on a metro station in the Wuhan metro system, China, are measured and compared in different scenarios. Results indicate that the performance of the evacuation efficiency can be significantly improved when the route planning strategy (that is specified in Scenario II) is implemented during the pedestrian evacuation. The developed approach can provide valuable theoretic and practical insight into a deep understanding of route planning strategies during the pedestrian evacuation, and thus, the improvement of safety and economic objectives can further be achieved in the design or re-design of metro evacuation systems.     

The building blocks of walkability: Pedestrian activity in Abu Dhabi city center

This study develops an empirical approach that underlines the effect of land use mix and development grain on pedestrian movement in the streets and public spaces of urban neighborhoods. The study begins with the end in mind; it compares two urban sectors in Abu Dhabi city with broadly recognized contrasting levels of pedestrian movement. The research works backward to identify the combination of built environment attributes that result in differing levels of pedestrian activity between the eastern and western sectors of Abu Dhabi city center. Using Geographic Information Systems maps/data files, direct observations, and field metrics, the study computes various indices related to land use mix, density, and street connectivity for Abu Dhabi central business district. The findings of this study highlight the land use, spatial and street network configurations that enhance pedestrian activity in urban centers. From a local perspective, the research outcome would inform future visions aimed at transforming the city of Abu Dhabi into a global metropolis that provides its citizens and visitors with unique and vibrant urban settings conducive to intra- and inter-neighborhood walkability.     

基于公共安全的城市广场步行空间景观设计研究——以重庆市三峡广场为例

物质空间和人口的高密度发展促进城市快速发展,广场的更新速度与城市发展不同步,步行空间安全系数降低,安全事故发生的概率增大,公共景观作为广场步行空间的构成要素影响步行空间的安全。以重庆市三峡广场为研究对象,基于层次分析法—模糊综合评价法从绿化、道路、水景设计以及景观小品等方面开展景观安全评价,明确景观安全性设计的重点,发现其存在的安全隐患,实现安全评价定性分析与定量计算的有机结合,为广场步行空间公共景观安全性设计与评价提供参考。     

The layered city: pedestrian networks in downtown Santiago and their impact on urban vitality

A distinctive feature of downtown Santiago is its three-layered pedestrian network, consisting of streets, pedestrian zones and commercial galleries. This research shows that an important part of the vitality of downtown Santiago is because of its physical and configurational structure of streets, pedestrian zones and commercial galleries. This three-layered pedestrian network has been able to introduce a progressive differentiation of pedestrian flows into the urban block, thereby allowing for lower rents and the diversification of retail, which in turn facilitates the social diversity of service providers and users in the historic centre of Santiago.     

上海世博会浦东园区高架平台客流需求分析

2010年世博会将在上海举办。高架平台是世博会园区内人行交通系统的重要组成部分,会展期间将承担园区内的部分客流交通量。客流量是设施规划设计的重要依据。以上海世博会控制性详细规划和城市设计为基础,采用四阶段模型方法对园区内客流需求进行预测。以上海世博会为例,为大型主题活动的交通需求预测提供参考。     

Crowding Studies and Urban Life: A Critical Review

In recent years, a great deal of speculation and research has appeared on the topic of whether population density has serious social psychological consequences. In this article, we review the crowding literature with particular concern for its implications for urban life. First, we examine the extant research and draw two conclusions: that much of the work is methodologically or conceptually limited; and, that density, though perceived as unpleasant, does not appear to have definite and consistent detrimental effects. Second, we consider the theoretical relevance of this literature to urban studies, find it lacking in certain respects, and suggest solutions to the problem of relevance. Finally, we present several theoretical frameworks for guiding future research on the effects of urban density.     

以公交和步行为导向的当代城市中心区空间重塑策略研究

在当代高密度城市中心区,缓解人 车冲突和构建宜步行空间备受关注。文章选 取陆家嘴金融区作为案例,通过小陆家嘴的 空间发展梳理、空间结构分析和空间现状调 研,指出中心区空间存在空间格局机动化,主 轴切割城市空间,以及公共空间节点与步行 系统脱离等问题。同时采用图解和空间句法 等方法,对比研究TOD模式、巴黎德方斯、 维也纳多瑙新城、伦敦金丝雀码头等一组基 于公交化和步行化理念开发的城市中心区, 提出优化中心区步行空间的主要内容在于构 建宜步行的交通结构,提升公共交通对步行 者的支持和塑造能激发城市生活的公共空 间。基于此,提出包括立体化交通策略、站厅 核策略、可见即可达的步行空间主节点策略 等适用于当代城市中心区空间重塑的措施, 为后续中心区建设和改造提供思路。     

Effects of perceived indoor temperature on daylight glare perception

This research investigates the effects of perceived indoor temperature on glare sensation. A laboratory experiment was carried out where volunteers (n?=?19) performed an office-like computer task. Three scenarios with sunspots over the desk were evaluated: a cold scenario, a comfort scenario and a hot scenario. All had the same vertical illuminance at the eye and luminance ratios. Discomfort glare was measured with the predictive daylight glare probability (DGP) model; actual perception of glare was assessed with glare sensation vote (GSV) scale; while thermal comfort was evaluated with thermal sensation vote (TSV) scale. In order to know how much the perceived temperature contributes to the model, an ordinal regression was performed. The result showed a Nagelkerke pseudo-R²?=?0.52, p =?0.001, indicating that the perceived temperature affected glare predictions. This is an improvement in the understanding of daylight glare, which will allow researchers and practitioners to make informed decisions about sustainable design and occupant comfort. In conclusion, a more comprehensive glare model should include perceived temperature as a variable of the current glare model. Also, the results suggest that DGP should be used only when the person is in thermal comfort.     

Understanding pedestrian behavior and spatial relations: A pedestrianized area in Besiktas,Istanbul

This research provides a mixed method of investigating and analyzing pedestrian behavior in pedestrianized areas, which is one of the human-based urban development practices. The relationship between pedestrian behavior and perception of the city is discussed through a combination of architect and urban planner Gordon Cullen's theory and Space Syntax methodology. This study examines the development and implementation of the methodology to understand the relationship between pedestrian behavior and space in Besiktas Koyici settlement, Istanbul. The methodology, integrated with on-site observations (observing 10 min at five different observation points in the settlement at predetermined times on weekdays and weekends), surveys (determining pedestrian movement and perception in terms of Cullen's theory) and spatial configuration (Space Syntax analysis (connectivity, integrity) done with DepthMapX software), aims to analyze pedestrian behavior patterns. The concepts of sense of place and content, as well as the effects of their sub-concepts on their behaviors, were revealed because of a survey conducted with students and architects of variety of educational levels who are daily users of the field. Pedestrian counting and observations were used to create density, activity, and mobility maps of the area. It has been found that pedestrianized areas have a significant impact on pedestrian behavior through influencing vitality and appeal and that Cullen's theory may be used to analyze pedestrian behavior and perceptions of the city. The study showed that spatial configuration and Cullen's theory effect pedestrian movement by complementing each other.     

Pedestrian-level wind environment near a super-tall building with unconventional configurations in a regular urban area

Unconventional configurations of tall buildings are noticeably different from their counterpart of traditional building designs but nevertheless, the unconventional configurations have often been adopted for tall buildings without their impact on the pedestrian-level wind environment (PLWE) fully understood. To fill the existing knowledge gap, this study investigates the PLWE near a 400 m super-tall building with various conventional and unconventional configurations in a regular urban area. Computational fluid dynamics (CFD) simulations were conducted for three incident wind directions (θ = 0°, 22.5°, and 45°) to investigate mean wind speed at the pedestrian level using the three-dimensional (3D), steady-state, Reynolds-averaged Navier-Stokes (RANS) technique. The results reveal 1.5- to 2.5-fold increase in maximum wind speed in the urban area after the construction of a super-tall building. The magnitude of the maximum wind speed and areas with high and low wind speeds in the PLWE, however, significantly vary with building design and incident wind direction. The configurations with sharp corners, large plan aspect ratios and frontal areas and the orientation consistently show a strong dependency on incident wind direction except the one with rounded plan shapes. The location of building openings and direction of building inclination are two other factors that modify the PLWE in an urban area. Moreover, the projected width of the super-tall building at a height slightly above the roof level of surrounding buildings is critical for estimating the areas of high and low wind speed at the pedestrian level.

     

LAI based trees selection for mid latitude urban developments: A microclimatic study in Cairo, Egypt

To study the leaf area index, LAI, based thermal performance in distinguishing trees for Cairo's urban developments, ENVI-met plants database was used as platform for a foliage modeling parameter, the leaf area density, LAD. Two Egyptian trees; Ficus elastica, and Peltophorum pterocarpum were simulated in 2 urban sites with one having no trees, whilst the second is having Ficus nitida trees. Trees LAD values were calculated using flat leaves' trees LAI definition to produce maximum ground solid shadow at peak time. An empirical value of 1 for LAI is applied to numerically introduce LAD values for ENVI-met.Basically, different meteorological records showed improvements for pedestrian comfort and ambient microclimate of the building using F. elastica. About 40–50% interception of direct radiation, reductions in surfaces' fluxes around trees and in radiant temperature T_mrt in comparison to base cases gave preferability to F. elastica. The lack of soil water prevented evapotranspiration to take place effectively and the reduced wind speeds concluded negligible air temperature differences from both base cases except slightly appeared with the F. elastica. Results show that a flat leaves tree if does not validate LAI of 1, the ground shading would not fulfill about 50% direct radiation interception and this value can be used as a reference for urban trees selection.Further simulations were held to investigate LAI value of maximum direct radiation interception.Performing additional simulations, F. elastica of LAI of 3 intercepted almost 84% of direct radiation and revealed implications about urban trees in practice and its actual LAI.     

城市步行交通系统规划研究

随着现代城市的发展,步行空间及其体系日益受到人们的关注与重视,它对于改善城市的环境质量和塑造城市特色能够起到十分重要的作用。本文介绍了我国步行交通现状及其特征,阐述了建立步行通道系统的必要性,并对步行通道系统规划建设的重点进行了探讨,以山海关关城步行区为实例进行了说明,指出应以“以人为本”为出发点,在中心区步行街改造、公交捷运换乘、行人过街设施等方面完善城市步行交通系统。     

Assessing the potential for real-time urban flood forecasting based on a worldwide survey on data availability

This paper explores the potential for real-time urban flood forecasting based on literature and the results from an online worldwide survey with 176 participants. The survey investigated the use of data in urban flood management as well as the perceived challenges in data acquisition and its principal constraints in urban flood modelling. It was originally assumed that the lack of real-time urban flood forecasting systems is related to the lack of relevant data. Contrary to this assumption, the study found that a significant number of the participants have used some kind of data and that a possible explanation for so few cases is that urban flood managers or modellers (practitioners) may not be aware they have the means to make a pluvial flood forecast. This paper highlights that urban flood practitioners can make a flood forecast with the resources currently available.     

Understanding the Legacy of Pedestrian Malls

Abstract

Problem, research strategy, and findings: In the postwar period, cities in the United States installed pedestrian malls to support downtown retail as suburbanization lured shoppers to malls on the periphery. Many cities removed their malls after downtown retail continued to falter. This failure has fostered a negative perception of pedestrian malls among city planners and the general public. In this research I re-examine pedestrian malls as public space and ask why some cities removed their malls while others remain. I compiled a catalog of all 140 pedestrian malls built between 1959 and 1985 that provides the data to understand the full scope of the phenomenon during this era. The catalog also includes data that tests hypotheses about why some pedestrian malls survived, including climate, proximity to a university, and nearby population. I supplement the catalog with a survey of pedestrian mall managers to understand the role of renovation and management in their survival. The results show pedestrian malls are more likely to survive in places with temperate climates, near universities, and in growing cities, though there are exceptions. City governments or business improvement districts actively manage many remaining malls, and programming and periodic renovations have helped them remain vibrant.

Takeaway for practice: Old pedestrian malls failed because cities installed them to save retail and did not consider the fundamentals of placemaking when siting and designing them. Many remaining pedestrian malls are in areas with high pedestrian volumes. Cities have continued to design and manage these spaces according to best practices. Planners considering new pedestrian spaces should not be deterred by the history of old pedestrian malls, as long as they choose their site carefully and manage the space to keep it safe, clean, and inviting.     

Smart growth and goods movement: emerging research agendas

While recent urban planning efforts have focused on the management of growth into developed areas, the research community has not examined the impacts of these development patterns on urban goods movement. Successful implementation of growth strategies has multiple environmental and social benefits but also raises the demand for intra-urban goods movement, potentially increasing conflicts between modes of travel and worsening air quality. Because urban goods movement is critical for economic vitality, understanding the relation between smart growth and goods movement is necessary in the development of appropriate policies.

This paper reviews the academic literature and summarizes the results of six focus groups to identify gaps in the state of knowledge and suggest important future research topics in five sub-areas of smart growth related to goods movement: (1) access, parking, and loading zones; (2) road channelization and bicycle and pedestrian facilities; (3) land use; (4) logistics; and (5) network system management.     

高密度城市公共活动中心多层步行系统更新研究

步行环境恶化和公共空间缺失是 当前主要的城市问题。针对国内现有公共活 动中心区步行环境的实际情况,提出四种可 行的建设模式,继而以上海五角场和徐家汇 为例,具体阐释多层步行系统的可行模式及 其所带来的地区活力。通过案例阐释,得出网 络化、立体化的多层步行系统适应于当前国内 大多数高密度城市公共活动中心区城市再更 新这一结论,但也指出,应通过多种评估来定 量剖析公共中心区步行空间实际需求,实现城 市精细化设计。     

Recent developments in pedestrian flow theory and research in Russia

Predtechenskii and Milinskii's seminal work [Predtechenskii VM, Milinskii AI. Planning for foot traffic flow in buildings. Revised and updated edition. Moscow: Stoiizdat; 1969] in relation to pedestrian flows is well known. However, analysis of the experimental results and observations obtained from this series of experimental studies revealed the inherent statistical non-homogeneity of pedestrian flow speeds [Kholshevnikov VV. The study of human flows and methodology of evacuation standardisation. Moscow: MIFS; 1999]. As such, the results of these individual experiments cannot be integrated to produce a valid general expression V=f(D) for each type of pedestrian flow path, where V is the flow velocity and D is the flow density. This paper presents further pedestrian flow research conducted in Russia post 1969.     

Towards a Deleuzoguattarian methodology for urban design

The philosophy of Gilles Deleuze and Felix Guattari (Deleuzoguattarian) is now widely thought to be apropos for today’s world. This paper proposes Deleuzoguattarian philosophy as a new methodology for urban design research and practice. First, existing methodologies in the field of urban design are examined and their strengths and limitations outlined in relation to current urban problems. A reading of Deleuzoguattarian philosophy from an urban design perspective is then provided in order to propose a new methodology for research and practice. This reading mainly concentrates on the ontology and epistemology offered by the philosophy, aspects that have been neglected in the literature. The concept of territorialization as a complementary concept to assemblage theory is highlighted in order to illustrate the characteristics of the ontology and epistemology. Finally, normative goals are discussed. It is concluded that Deleuzoguattarian philosophy is not only an ethical response to modernism but is an epistemological need.     

面向城市高密度街区舒适风环境的设计策略研究——以北京三条商业街的实地数据分析为例

城市建筑布局与城市外部风资源的相互作用决定了城市建成环境内部风环境的特征,对城市热岛效应、建筑能耗、建筑室内外的热舒适、空气质量以及居民健康都具有一定的影响作用。本研究试图避免复杂且高成本的计算机模拟,而基于常年大量现场测试的物理环境指标,采用数据统计分析的方法,通过相对简单的城市建成环境的形态参数和外部城市风环境获取步行街区行人高度下的微环境风速,而同时又保证风环境关键信息的可接受精度和准确性。研究数据的获取主要基于北京王府井步行街、前门大街、大栅栏商业街三处街区环境,并同步采集了城市外部的风向与风速数据。提出并建立的城市行人尺度下的风环境模型能够更加有效地应用于高密度城市区域规划与设计实践的初步设计阶段。