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trJ N 0ANNUAL INTERNATIONAL CONFERENCE
PROCEEDINGS
�
7
th
Annual International Con£ erence on
Architecture and Civil Engineering
(ACE 2019)
Organized & Published by
STEERING INNOVATION, SERVING
Global Science and Technology Forum
www.globalstf.org
Indexed by
Scopus
7
th
Annual International Conference on
Architecture and Civil Engineering
(ACE 2019)
27th – 28th May 2019
Singapore
Organized & Published By
Global Science and Technology Forum
www.globalstf.org
This book contains a collection of abstracts presented at the 7th Annual International Conference on
Architecture and Civil Engineering (ACE 2019) organized by Global Science and Technology Forum
in Singapore on 27
th– 28
thMay 2019.
This conference continuously aims to foster the growth of architecture and civil engineering and its
benefits to the community at large. The comprehensive content of this conference has attracted immense
attention and the wealth of information spread out over all the papers would be extremely useful to
professionals working in the related fields.
This book, or parts thereof, may not be reproduced in any form or by any means, electronic or mechanical,
including photocopying, recording or any information storage and retrieval system now known or to be
invented, without written permission from the Publisher.
Organized, Published and Distributed by
Global Science and Technology Forum (GSTF)
7th Annual International Conference on Architecture and Civil Engineering (ACE 2019)
Tel: +65 6327 0166 Fax: +65 6327 0162
www.globalstf.org |
[email protected]
E-mail:
[email protected]
Website:
http://ace-conference.org
7th
Annual International Conference on Architecture and Civil Engineering (ACE 2019)
Print ISSN: 2301-394X, E-Periodical ISSN: 2301-3958
This book, or parts thereof, may not be reproduced in any form or by any means, electronic or mechanical,
including photocopying, recording or any information storage and retrieval system now known or to be
invented, without written permission from the Publisher.
Copyright © GSTF 2019
All rights reserved.
The accuracy of all materials appearing in the paper as part of the proceedings is the responsibility of the authors alone. Statements are not necessarily endorsed by the organizers of ACE 2019, members of the Programme Committee or associated supporting organizations.
We are happy to present you with Proceedings of the 7th Annual International Conference on
Architecture and Civil Engineering (ACE 2019) organized by the Global Science and Technology
Forum in Singapore on
27
th– 28
thMay 2019.
This conference serves as a forum for scholars, policy makers, experienced professionals, and business
executives to present and exchange new ideas in broad fields of Architecture, Civil Engineering and
related disciplines. The accepted papers were selected by considering the scope of the work, quality of
the research presented and organization and structure of the overall papers. The papers were selected
and organized to include a broad spectrum of conference themes, in order to give broad exposure of
diverse work and ideas to attendees of the conference. All the papers selected for presentation at this
conference and for publication in the proceedings have been subjected to double blind peer review.
We thank all review committee members, partner universities, organizing committee members, and
especially all the conference participants for making this conference an on-going success. We hope that
the participants will benefit from their contributions to the Proceedings of ACE 2019 and trust that this
volume will be useful in all of the conference participants’ future research endeavors.
Editors in Chief
Peter C. O. Anderson
Professor of Architecture
California College of the Arts, San Francisco, USA
Mark S. T. Anderson
Professor of Architecture
University of California, Berkeley, USA
Editorial
This volume of conference proceedings contains a collection of research papers presented at the
7th
Annual International on Architecture and Civil Engineering Conference organized by Global Science
and Technology Forum in Singapore on 27
th– 28
thMay 2019.
The ACE 2019 conference is an international event for the presentation, interaction and dissemination
of new advances relevant to architecture and civil engineering. As chairman of the Board of Governors,
GSTF, I would like to express my sincere thanks to all those who have contributed to the success of
ACE 2019.
A special thanks to all our speakers, authors and delegates for making ACE 2019 a successful platform
for the industry, fostering growth, learning, networking and inspiration. We sincerely hope you find the
conference proceedings enriching and thought-provoking.
Professor the Hon. Dr. Stephen Martin
Chairman, Board of Governors, GSTF
Foreword
We are pleased to welcome you to the 7
thAnnual International Conference on Architecture and Civil
Engineering (ACE 2019). ACE 2019 continuously aims to foster the growth of research in architecture
and civil engineering and its concomitant benefits for the community at large. The research papers
published in the proceedings are comprehensive in that they contain a wealth of information that is
extremely useful to academics and professionals working in this and related fields.
It is my pleasure to announce the participation of leading academics and researchers in their respective
areas of focus from various countries at this event. The Conference Proceedings and the presentations
made at ACE 2019, are the end result of a tremendous amount of innovative work and a highly selective
review process. Am happy to announce that there will be author delegates from 70 universities in
45 countries to attend ACE 2019.
We have received research papers from distinguished participating academics from various countries.
There will be “BEST PAPER AWARDS” for authors and students, to recognize outstanding
contributions and research publications.
We thank all authors for their participation and are happy that they have chosen ACE 2019 as the
platform to present their work. Credit also goes to all Program Committee members and Review Panel
members for their contributions in reviewing and evaluating the submissions and for making ACE 2019,
a success and for increasing the standing of this annual conference from year to year.
Dr. Anton Ravindran
CEng (UK), FBCS,FSCSPresident, Global Science and Technology Forum
Preface
Editor-in-Chief
Prof. Mark S. T. Anderson
Department of Architecture
College of Environmental Design
University of California, Berkeley, USA
Co-Editor
Prof. Peter Anderson
Department of Architecture
California College of the Arts, USA
Program Committee Members Prof. Clark E. Llewellyn
University of Hawaii at Manoa, USA
Assoc. Prof. Gregory D. Thomson
University of Wisconsin, USA
Prof. Ralph E. Hammann
University of Illinois at Urbana-Champaign, USA
Prof. James Wines
Penn State University, USA
Prof. Botond Bognar
University of Illinois at Urbana-Champaign, USA
Prof. Fatih Ahmet Rifki
Montana State University, USA
Assoc. Prof. Kevin Erickson
University of Illinois at Urbana-Champaign, USA
Assoc. Prof. Phillip B Gallegos Jr.
University of Colorado Denver, USA
Prof. Tulio Sulbaran
The University of Southern Mississippi, USA
Assoc. Prof. Sergio Palleroni
Portland State University, USA
Assoc. Prof. John E. Folan
Mellon University, USA
Assoc. Prof. Blaine Brownell
University of Minnesota, USA
Asst. Prof. Ronald B. Lumpkin
Florida A&M University, USA
Dr. Rafaat M. Morsi Hussein
State University of New York (SUNY), USA
Daniel Joseph Whittaker
Illinois Institute of Technology, USA
Asst. Prof. Julian Wang
University of Cincinnati, USA
Prof. Richard Laing
Robert Gordon University, UK
Prof. David Chua Kim Huat
National University of Singapore
Assoc. Prof. Nalanie Mithraratne
National University of Singapore
Assoc. Prof. Erik L’Heureux
National University of Singapore
Prof. Ljubomir Jankovic
Birmingham City University, UK
Asst. Prof. Cho Im Sik
National University of Singapore
Assoc. Prof. Trivic Zdravko
National University of Singapore
Prof. Mark Dorrian
Newcastle University, UK
Prof. Ruth Conroy Dalton
Northumbria University, UK
Prof. Steve Garrity
University of Leeds, UK
Prof. Stefan Schäfer
Technical University of Darmstadt, Germany
Prof. Arto Kiviniemi
University of Liverpool, UK
Assoc. Prof. Mohamed Osmani
Loughborough University, UK
Dr. Gabriel Tang
Sheffield Hallam University, UK
Dr. Albena Yaneva
University of Manchester, UK
Prof. Debasish Roy
Indian Institute of Science, Bangalore,India
Dr. Kathryn Moore
Birmingham City University, UK
Prof. Alessandro Bianchi
Politecnico di Milano, Italy
Prof. Bernhard Sill
Trier University of Applied Sciences, Germany
Dr. Georgios Kapiogiannis
Anglia Ruskin University, UK
Program Committee
Dr. Marta Pieczara
Poznań University of Technology, Poland
Dr. Grzegorz Woroniak
Bialystok University of Technology, Poland
Assoc.Prof. Sabina Kuc
Cracow University of Technology, Poland
Assoc. Prof. Adrian Carter
Aalborg University, Denmark
Assoc. Prof. Jonas Jakaitis
Vilnius Gediminas Technical University, Lithuania
Prof. Avi Friedman
Mcgill University, Canada
Prof. Amir Fam
Queen’s University, Canada
Prof. Greg Andonian
Carleton University, Canada
Assoc. Prof. Elizabeth English
University of Waterloo, Canada
Assoc. Prof. Roger Connah
Carleton University, Canada
Assoc. Prof. Manuel Baez
Carleton University, Canada
Prof. Luis Feduchi
The University of Queensland, Australia
Prof. Srinath Perera
Western Sydney University, Australia
Assoc. Prof. Lu Aye
The University of Melbourne, Australia
Assoc. Prof. Bill Wong
Monash University, Australia
Dr. Kelly Greenop
The University of Queensland, Australia
Mr. Omid Reza Baghchesaraei
Western Sydney University, Australia
Prof. Janis Birkeland
Queensland University of Technology (QUT) University of Auckland, New Zealand
Dr Shankha Pratim Bhattacharya
Indian Institute of Technology Kharagpur, India
Mahua Mukherjee
IIT Roorkee, INDIA
Dr. Meenakshi Singhal
Guru Nanak Dev University, Amritsar INDIA
Prof (Dr) Ranjana Mital
Indraprastha Estate New Delhi, India
Dr. Kasthurba AK
National Institute of Technology Calicut
V.Devadas
Indian Institute of Technology Roorkee
Prabhjot Singh Chani
Indian Institute of Technology Roorkee
Eng. Elaine R. Rivera
Saint Louis University, Baguio City, Philippines
Dr. Anwar Khitab
Mirpur Univrsity of Science and Technology, Pakistan
Dr. Simona Canepa
Politecnico di Torino, Italy
Prof. Robert Powell
Taylor’s University, Malaysia
Prof. Dr. Natascha Meuser
Anhalt University of Applied Sciences, Germany
Prof. Dirk Junker
University of Applied Sciences, Germany
Prof. Dr. Ing. Borislav Hristov
University of Applied Sciences (HTW Berlin)
Dr. Jacky Y. K. Ng
City University of Hong Kong
Dr. Ana Silvia Aguilera Vieyra
Hiroshima University, Japan
Dr. N. Aravind
Caledonian College of Engineering Sultanate of Oman
Assoc. Prof. Junshan Liu, MBC
Auburn University
Prof. Dr. Vasco André Barbosa Brandão
University of La Sabana, Colombia
Asst.Prof. Mohammad Arif Kamal
Aligarh Muslim University,India
Dr. Arati S. Petkar
College of Engineering, Pune
Dr. Nedhal Al-Tamimi
Najran University, KSA
Dr. Sarika Bahadure
Visvesvaraya National Institute of Technology Nagpur, India
7th Annual International Conference on
Architecture and Civil Engineering (ACE 2019)
ARCHITECTURE CIVIL ENGINEERING AND URBAN PLANNING
Unlocking the Architecture of Eccentric Braces
1
R.Gary Black
Effect of Symmetric and Asymmetric Widening of Tunnel on Rock Mass Behaviour in Various Rock
Types and In Situ Stress State
8
Babar Khan, Turab H. Jafri, S.Muhammad Jamil
Process Framework for Architectural Design
18
Praful Gharpure
Study on the Modern Bank Architecture in Tianjin
22
Liu Chengming, Liu Tongtong, Zhu Yang
A Study on the Structural Performance of High-rise Elevator Attached to Bridge Tower
32
Li Dong, Yizhuo Zhang
The obstructions scenario in evacuation: Simulation of urban evacuation vulnerability and its solution
37
Nattasit Srinurak, Nobuo Mishima, Janjira Sukwai
Do neighborhoods affect active park use: A study on urban parks’ characteristics in Chiang Mai
Municipality in Thailand
44
Janjira Sukwai, Nobuo Mishima, Nattasit Srinurak
Post Occupancy Evaluation for Resident Satisfaction of Public Housing in Lucknow, India
52
Anjali Pathak, B K Das
Research on the Public Space of Urban Village in Nantou Ancient Town of Shenzhen
58
Fan Luo, Yuan Wang
Editorial
iii
Foreword
iv
Preface
v
Program Committee
vi
Author Index
685
Table of Contents
viiiSpatial Site Reference, Analysis and Improvement: Jaffna Town Center Development Under
Post War Context
63
Kabilan. S.
Architecture as Art of Interior
73
Myungshig Kim
A Study of the Advantages and Sustainability of PEX Piping
79
Junshan Liu, Scott Kramer, James D. Vigil
Measuring Urban Accessibility using Complete Spatial Randomness
85
Sarika Bahadure, Tanushri Kamble
Appraisal of residential satisfaction in slum rehabilitation housing in Mumbai
91
Bangkim Kshetrimayum, Ronita Bardhan
Design of Landmark Pedestrian Urban Bridge with Evolutionary Topology Optimization
100
Hamide Soroush, Hamid Aliakbarlou, Roham Afghani Khoraskani, Mohammadreza Hafezi
Urban Land use assessment of Nagpur City through Change Detection
110
Meenal Surawar
Architectural context: Meanings and interpretations to support the project design approach
121
Chadi El Khoury
Economic Study of Designing Nearly Zero Energy Houses in the Desert Region of Jordan
127
Anwar F. Ibrahim, Hikmat H. Ali, Razan Rashid
Development and implementation of a quantitative multi-metrics methodology to characterize urban
Permeability
134
Carlo Andrea Biraghi, Giulia Ceriotti, Giovanni Porta, Massimo Tadi
Acoustical Comfort in Office Buildings
145
Deniz Artan, Esin Ergen, Isilay Tekce
Risk Management Practices in a developing country setting: The Philippine experience
150
Richmon B. Pangilinan, Arlheth P. delos Angeles, Orlean G. dela Cruz
Visualising software with local accuracy for urban designers
156
Sarosh Mulla, Aaron Paterson, Daniel Christev
Evaluation of International Roughness Index by Speed-Related Quality Criteria in the Philippines
160
Juland A. Padilla, Armando N. Victoria Jr., Orlean G. dela Cruz, Carlota T. Despabeladera,
Cristene Joy N. Creencia
Enhancing the Mechanical Properties of Fiber Reinforced Geopolymer Concrete
165
Sara Mustafa, Said Elkholy, Hilal El-hassan, Mona Megahed, Esma Vall, Khalas Alshehhi
Perspectives for Flood Risk Assessment and Environmental Management for Drainage System in
Sakon Nakhon Municipality, Sakon Nakhon Province, Thailand
170
Piyanuch Jaikaew, Pitak Paksanondha
Urban Conservation Values: The Case of Al-Saqqaf Palace Area, Makkah
175
Marwa Abouhassan
Case Studies on Passive Design Strategies of Research Labs Based on Facade and Building Mass
184
Jinho Kim
Factors affecting Urban Land Valuation and Practices in India
190
Preeti Jaiswal, Pooja Nigam, Satish Pipralia
Behaviour Setting Theory and the rejuvenation of the Royal Town of Klang, Malaysia
196
Robert Powell, Camelia Kusumo
Kaki-Lima: Why We Should Keep Five-Footways in the Historic Core of Klang
205
Camelia Kusumo, Robert Powell
Scrap Housing: A low-cost sustainable approach towards in situ slum rehabilitation and redevelopment
in Kolkata
212
Hitesh Vyas, Haimanti Banerji
The Influence of Temporary Works Designers on Construction Ergonomics
222
John Smallwood
Understanding the Contributing Factors to Nighttime Crashes at Freeway Mainline Segments
227
Hongyun Chen, Kristiansson Fanny
SUSTAINABLE ENERGY AND ENVIRONMENTAL SCIENCES
Enhancing Indoor Health Comfort in Adaptively Reused Heritage Building
228
Susan, Dyah Kusuma Wardhani
Greenship Assessment of Indoor Health Comfort in Adaptive Reused Building
236
Dyah Kusuma Wardhani, Susan
Insulation and Ventilation of Poultry Houses Considering Seasonal Climate in South Korea
245
Young Cheol Kwon
Guidelines to utilize the Wind catcher “Malqaf” technique in Jeddah's new residential buildings
255
Mady Mohamed, Mohamed F. El-Amin, Mohammed Mohammed, Aida Nayer, Samir Felmban
Dubai Creek Extension - A man-made water canal dredged and extended to form a Waterfront
Development within the Urban Fabric of Dubai City
267
Ahmed Hammad
Thermal Performance of Living Walls in Thailand
272
Sasima Charoenkit, Suthat Yiemwattana, Ninnart Rachapradit, Srisangwan Laywisadkul,
Nattika Navapan, Thanasarn Changnawa
Seismic Hazard Analysis and Obtaining Uniform Hazard Spectra for Rasht Region, Iran
278
Hamid Aliakbarlou, Amirali Hadinejad
Living in the green on the top
New way of living in Turin city centre
285
Simona Canepa, Marco Vaudetti
Market as Social Space: A Study of Everyday Socio-spatial Practices in Thailand
294
Nattika Navapan, Sasima Charoenkit
Role of Green and Open Urban Spaces in Developing and Promoting Valuable Residential Areas
300
Baher Ismail Farahat
Qualitative GIS for Strategic Planning of Sustainable Transportation
311
Jianling Li, June Chae-Un Sin
Nomads’Quality of Life; Sustainability, in the Built Environment
319
Omar Musa Amireh, Dania Hasan Ali Al-Harasis, Zaineh Sameh Abu Omar
Function follows phototropism: Understanding lights as a component of urban infrastructure
326
Dania Hasan Ali Al-Harasis, Zaineh Sameh Abu Omar, Omar Musa Amireh
Urban Transport Policies in India in the Respect to Climate Change: Case Study of Bengaluru City,
Karnataka, India
331
Ajay Kumar, Amit Kumar Bala
Temporary Landscape Interventions
Ephemeral Green and Art installations in urban situations and landscape urbanism
340
Karl H.C. Ludwig
Healing Landscapes In The Multyfunctional Hybrid Objects
347
Elena Y. Zaykova
The smartest location for an eco-district– -investigation of urban spatial energy efficiency
356
Julia Kurek, Justyna Martyniuk-Pęczek
Sustainable Urban development in Historic Areas
365
Marwa Abouhassan
Assessment and Strategies for Urban Green Spaces: Case of Hyderabad
374
Sweta Bhupatiraju, Uttam Kumar Banerjee
Assessment of the Interrelationship between Waterfront and the Adjacent Neighborhood: Case of
Gwarighat, Jabalpur
383
Shikha Kosta, Uttam Kumar Banerjee
A quest for networked city in developing countries by spatial assessment of the status of urban water
system: A case of Jaipur city
392
Manish Sharma, Nand Kumar, Ashwani Kumar
Flood Exposure of Shenzhen from Past to Future: A Spatio-Temporal Approach using Urban Growth
Modeling
400
Gizem Mestav Sarica, Tinger Zhu, Tso-Chien Pan
406
416
425
429
434
442
447
453
460
466
472
477
483
492
500
Triple Net Zero Bioclimatic Canine Oasis (Net Zero Home and Communities)
Anne Nicole J. Villarruz
Assessing Urban Energy Efficiency Strategies Adopted By Cities
Manas Vijayan, Sarika Bahadure
Effect of different wind speeds on a seismically designed high-rise building according to different
resisting systems
Aya Diab, Youmn Al-Rawi
Sustainable Walkway Design in Hot Climate; Case Study of Abu Dhabi Corniche, UAE
Yaman Alhams, Mahmoud Haggag
Sustainable Pedestrian Infrastructure: A Walkability Assessment in Colombo
Thilini Sashinika, Shaleeni Coorey
Towards sustainable city. Is there a place for single family housing in the city of tomorrow?
Patrycja Haupt
Liquefaction-induced settlement and pore pressure during earthquake
Sunita Kumari, Amrendra Kumar
The Marriage Between Architecture and Sustainability. Algae Based towers
A New Proposal For Tower Design In Egypt
Khaled Dewidar, Marianne Nabil Guirguis, Ahmed Ehab Abdelsalam AEH
Post Occupancy Evaluation of Thermal Comfort in University Campus’s Open Spaces in Hot Arid
Region
Siba Adel Awawdeh
SMART HOMES, SMART CITIES, SMART NATIONS BY IOT
Self-organizing small-world graphs (
Case of urban arterial road networks )
Jeeno Soa George, Saikat Kumar Paul
Natural terrain and urban form : Interpreting locational patterns of arterial roads and activity centres
Jeeno Soa George, Saikat Kumar Paul, Richa Dhawale, Ankita Patnaik
The Ramifications of Teaching Design Studio Online
Jon Daniel Davey
The Next Generation Learning Technology In Urban Planning And Property Development
Michael Brazley
Strengthening the Learning of Structures through Graphics Integration – A Continuing Study
Bronne C. Dytoc
Wind Pressure Analysis of Movable Shading by Using CFD
Kyung-Ju Hwang, Gee-Cheol Kim, Yu-Seong Kim
Study on the Spatial Pattern and Influencing Factors of Business Services in Wuhan Metropolitan
Area, China
505
Zilu Ma, Yaping Huang
Analysis of current pedagogical approach for Technical Subjects in Architecture Education: A case
study of Architecture schools in Ahmedabad
512
Shreya Parikh, Archana Baghel, Dhara Dave
BIM Standards in Hong Kong: Development, Impact and Future
519
Han Hsi Ho
The accuracy of BLE Beacon for analyzing space usage patterns of non-sedentary users in NWW office
528
Jae Hoon Ma, Seung Hyun Cha
Housing Optimize Based on Unitize and Modularize
533
Chung Yi, Jiang Yong, Chen Da Peng
Lean six sigma as approach for developing sustainable architecture and urbanism
537
Samia Kamal Nassar
Patient and Clinician-Centric Healthcare Enhancement through Speech Recognition: A Research
Proposal
549
Gregory Thomas
A New Densification Approach For Upgrading The Vertical Public Realm And City Vitality
A new paradigm shifts towards Sustainable Vertical Urbanism
554
Ahmed Ehab Abdelsalam AEH, David Nicolson Cole, Khaled Dewidar, Andrew Crompton
Application of Multi Criteria Decision Making (MCDM) in prioritisation of Road Network for
Maintenance and Rehabilitation (M&R) Works
563
Madhavendra Sharma, S. K. Suman, Pradeep Kumar
A Study on Adhoc Information Exchanges Along Big Data Terminology In A Construction Project
570
Abhishek Kumar, Anikesh Paul, J.Uma Maheswari
Design-Build interdisciplinary course at Tsinghua University
578
Jiang Yong, Wang Wei,Wang Deyu,Zhong Yi
Application of Affordance Structure Matrix in Designing Artefact’s Layout
581
Arundhati Akhouri, J.Uma Maheswari, Purva Mujumdar
Space Modification and Personalization in Public Housing: Case of Walk-Up Apartments in Sri Lanka
589
Kavindu Kularatne, Shaleeni Coorey, Ranjith Perera
Architectural Expression of Folk Belief
Layout and Space Modality of Rural Guandi Temple Architecture in The Context of Guangong Worship
599
Jia Fan, Wang Renxiang
Gendering of Spaces
603
Jayati Chhabra, Sarika Bahadure
Impact of tourism on spatial growth of the destination
613
Tagore Sai Priya Nunna, Ankhi Banerjee
Factors Influencing Employment Of Aging Construction Workers In Large Building Project
618
Chonticha Kamolcharoensaensuk, Petcharat Limsupreeyarat
Future-Tech: Infusing technology integration in architecture pedagogy
624
Adonis Cleanthous, Markella Menikou
Assessment of Social Housing Design in Dubai: Conventional Vs. Virtual Reality Participatory Tools
630
Khaled Galal Ahmed, Hamda Said Al Naaimi, Menatullah Mostafa Omar, Mona Megahed, Shaikha Abdulla
Alazeezi
Analysis of the Principles of Decision Making in Planning Systems; The case of Regulatory Planning
System in Cape Town, South Africa
637
Benard Acellam
Reinstituting Economic Development as a Public Good: PART 1 - Supply-side as the Path
643
Bruce Frankel, Emily Hepworth, Jonathan Sullivan
Reinstituting Economic Development as a Public Good: PART 2 - Demand-side as the Path
653
Bruce Frankel, Emily Hepworth, Jonathan Sullivan
R.B. Fuller’s Innovative Architectural Designs
664
Waldemar Bober, Marek Oktaba
Evaluation of Townships from Sustainability Perspective: a case from India
671
Ritika M. Vakil, Arati S. Petkar
Unmanned Aerial System (UAS) in the Sustainable Built Environment – From a
Tertiary Education Perspective in Hong Kong
679
Tsz Chun Lawrence Tse
7th Annual International Conference on
Architecture and Civil Engineering (ACE 2019) Copyright © GSTF 2019
ISSN 2301-394X
DOI: 10.5176/2301-394X_ACE19.588
Development and implementation of a quantitative
multi-metrics methodology to characterize urban
Permeability
Carlo Andrea BiraghiDepartment of Architecture, Built Environment and Construction
Engineering (ABC) Politecnico di Milano
Milano, Italy [email protected]
Giulia Ceriotti Departement of Civil and Environmental Engineering (DICA) Politecnico di Milano Milano, Italy [email protected] Giovanni Porta Departement of Civil and Environmental Engineering (DICA) Politecnico di Milano Milano, Italy [email protected] Massimo Tadi
Department of Architecture, Built Environment and Construction
Engineering (ABC) Politecnico di Milano
Milano, Italy [email protected]
Abstract— This study aims at highlighting a morphological
property of urban CAS (complex adaptive systems), Permeability, by introducing a set of quantitative metrics for its definition. It defines a strategy for the analysis of urban permeability, reproducible on any urban context. Our approach is multidisciplinary and moves from the idea that the urban structure can be seen as a porous medium where buildings represent solid elements and open spaces represent the pores. The selected metrics include concepts like tortuosity and constrictivity, which are routinely employed in fluid mechanics to characterize mass transport through porous domains. We showcase the proposed methodological framework on three different types of urban structure for three cities. The results highlights and quantify morphological differences between urban areas developed in different historical periods. Results are arranged in diagrams to provide a new objective perception of urban permeability as a synergetic emergence between constituent parts of the urban fabric.
Keywords—morphology, urban design, permeability, complex adaptive system, porous media.
I. INTRODUCTION
In the last two centuries, the progressive and intense urbanization process has reshaped the role of cities: from simple human settlements, cities have become complex systems with multiple functions and nowadays they constitute the core of human activities and economy. Sustainable urban development is an important challenge that needs to be faced to support the continuous growth of cities and reduce their environmental impact, e.g., in terms of land use and energy consumption [1].
Single buildings are typically the target of the quantification and attempts of energy consumption reduction. However, the
total energy consumption recorded in cities is generally higher than the sum of buildings energy demand [2].
This suggests that a city cannot be considered as just an aggregation of disconnected buildings, but should be viewed as an ensemble of heterogeneous interconnected elements and subsystems. Urban elements evolve simultaneously in a nonlinear way as a Complex Adaptive System (CAS, [3]) which behaves and performs differently from the mere sum of disconnected elements. Striving to increase cities energy efficiency, any action performed on a single urban element necessarily provokes some transformations on all the other urban assets. As a consequence, urban planners must be aware that it might be possible to generate some positive or negative impacts on an urban element, indirectly, by modifying another part of the city system. Then, each urban element behavior cannot be analyzed and interpreted as a stand-alone but it is an emergence of a complex action-reaction mechanism resulting from all urban elements interconnection. In this regard, it is first essential to develop and apply suitable methodologies with the aim of i) describing and understanding the complexity of the cities and the relationships linking urban constituting elements, ii) quantifying cities morphological proprieties and iii) quantitatively explaining cities’ energy efficiency and sustainability through their attributes [4]. Many authors (e.g., [5;6;7;8;9;10]) have tackled these research questions aiming at defining quantitative metrics which could encode a reliable description of the urban system. However, an agreed set of indicators has not been found yet.
In this work we follow the principles of the Integrated Modification of Methodology (IMM, [2]) according to which the complexity of the urban structure can be described as a superimposition of different morphological and functional layers: Volume, Void, Function, and Transport. Considering 7th Annual International Conference on Architecture and Civil Engineering (ACE 2019)
this classification, each element and sub-system constituting the urban structure can be included in one of these layers. The peculiar behavior of each different urban system is the result of the way these layers interact with each other. The emergences of layer interactions can be quantified by a set of indicators that are called Key Categories (KCs): Porosity, Permeability, Diversity, Proximity, Effectiveness and Accessibility. The crucial challenge is encompassed by the need of providing a quantitative and objective definition of the selected KCs.
The work of Tadi et al. [4] poses the first step in this direction by investigating the concept of urban Porosity (the first KC) as the expression of the arrangements between building and urban void. The authors define six different quantitative metrics assessing different aspects of urban Porosity and supporting the idea that the city Porosity concept can be better characterized by analyzing simultaneously all the six metrics. Our work configures as a natural follow-up of the work of Tadi et al. [4] on Porosity: we now aim at exploring the concept of urban Permeability (the second KC) as the ensemble of urban morphological assets that controls the flows of people, vehicles or material [11].
The concept of urban Permeability is still debated in literature and alternative definitions have been provided. The literature presents two possible interpretation of the concept of urban Permeability: the visual and the physical one. Visual Permeability is related to the visibility of open and public pathways as opposed to private spaces which are excluded from visual contact with public spaces. In this work, we focus only on physical Permeability, as defined by Bentley [12], i.e. the ability of the urban structure to allow people a choice to move into the urban network.
Previous works interpret the physical Permeability as the extent to which a two-dimensional plan area embeds accessible space [13] or allows pedestrian movement [14]. In this context the concept of Permeability becomes equivalent to the one of urban connectivity [15]. A suite of different metrics have been proposed to quantify urban connectivity through various indicators, such as the intersection density (number of intersection per given area) [16], block density (number of blocks per given area) [17] or block size based measure and route directness [18]. As reviewed by Ellis et al. [10], each one of these indicators has its own weaknesses and limitations in providing consistent explanations of the urban Permeability. Indeed, Kusumastuti and Nicholson [15] and Pafka and Dovey [5] demonstrate that the concepts of Permeability and connectivity are related but not interchangeable as an urban morphology can present a good street connectivity indicator and, at the same time, a poor level of Permeability.
More recent studies [19] revise the concept of Permeability highlighting that Permeability is not only a measure of the existence of a link between any two points of an urban area (i.e., the urban connectivity) but it should also embed the multiplicity of route choices between those points [5]. Then, Permeability should contemporary quantify the directness of
links and the density of connections in a transport network [20]. This gives to urban Permeability concept a more general meaning and significant role in relation with the walkability potential which is associated with movements of people within the city, whether by foot, bike, public transport or car [21]. The complexity and the multiple aspects associated with the concept of urban Permeability are still a subject of debate in the current literature and a general consensus on methodological quantitative framework to assess Permeability on the basis of a single measurable property is still lacking. The synthesis of this KC in a single value may be limiting and incomplete, similarly to what observed for Porosity, as discussed by Tadi et al. [4].
This study aims at providing quantitative measures that can pinpoint significant features of the spatial organization of the urban elements in order to characterize the concept of urban Permeability. To this end, we define a set of six quantitative metrics: Street Area (SA), Normalized Average Link Length (ALL_N), Directness (D), Constrictivity (βN), Tortuosity (Tor) and Topography (Top).
For each proposed metric, we provide a quantification procedure that is reproducible and easily exportable to any case study of interest. For testing the applicability of the proposed metrics, we implement them on a set of selected case studies. The six metrics for each case study are presented through Kiviat (or radar) diagrams. The concept of Permeability can be then characterized, quantified and discussed by collectively reading the six metrics together and in relation with each other. Through the implementation of the proposed characterization on different case studies, we discuss the ability of the suite of proposed metrics to describe and quantify the main features of urban Permeability for diverse urban structures, spanning from medieval to recent urban contexts.
The paper is organized as follows. In Section 2, we present the methodology and the quantitative metrics introduced as descriptive of urban Permeability. Section 3 presents the case studies on which we provide and exemplificative quantification of the proposed metrics. In Section 4, we discuss the results of the proposed metrics on the case studies presented in Section 3 and their ability to quantify the multifaceted concept of urban Permeability. Finally, Section 5 concludes the paper providing the implications of the presented metrics for the future development of the IMM.
II. METHODOLOGY
Moving from the idea that urban Permeability is a multi-faceted concept which cannot be condensed in a single numerical indicator, we propose to characterize this KC by relying on an appropriately defined suite of quantitative metrics. Each one of these addresses a different aspect of the concept of Permeability of an urban area.
7th Annual International Conference on Architecture and Civil Engineering (ACE 2019)
We then present here our methodology to characterize the Permeability of chosen delimited urban area according to six quantitative indicators: Street Area (SA), Normalized Average Link Length (ALL_N), Directness (D), Constrictivity (βN), Tortuosity (Tor) and Topography (Top). All these quantities are, on purpose, defined to vary between 0 and 1 which is helpful when the metrics need to be post-processed, interpreted and compared among different case studies. Some of these quantities are introduced here specifically for the characterization of Permeability on urban context (i.e., SA,
ALL, D and Top). Tortuosity and Constrictivity are, instead,
parameters that are commonly employed to characterize porous media across different scientific fields, e.g. in chemical engineering or geosciences. These parameters are here exported to cities under the assumption that the urban structure can be assimilated to a bi-dimensional porous medium. Indeed, there is a clear correspondence between morphological structures observed for bi-dimensional porous media and urban plans where buildings are represented by solid elements and open spaces (as streets and squares) can be interpreted as the voids of the porous domain. These latter are routinely characterized through by a number of effective parameters which describe and quantify the impact of porous medium properties on a wide range of physical processes of practical interest taking place in porous domains such as fluid flow, solute transport, chemical reactions, solid deformations [22].
In the following we introduce each one of the metrics concurring to Permeability description by providing its definition and the operational procedure employed to compute it. Along with the methodology presentation, we display some illustrative examples of the computed metrics which might help in visualizing the physical meaning of each quantity. The methodologies proposed for computing these metrics are reproducible and exportable to any case study since they make use of information that are typically found in topographical database and rely on freely available software. For our case studies, all located in Lombardy region (Italy), we rely on the DBT (Topographic Database,) of Lombardy, using the layers Street Network (L010107), Street Area (A010104), Street Nodes (P010108) and Volumetric Units (A020101).
2.1 Street Area
Street Area (SA) quantifies the portion of void space, which is open, continuous and accessible to urban flows. The open void space is spatially complementary to the joint area identified by buildings and bounded open spaces. These latter are isolated spaces completely enclosed by buildings, such as courts or other urban cavities.
We define the Street Area (SA) as
S v
A
SA
A
(1)The quantity AS indicates the accessible void area which can be extracted from the street area layer included in the DBT database (Topographic Database) or, alternatively, by computing it by summing the extension of streets, sidewalks and other paths. The quantity Av is the total void urban area computed as
A
v
A
t
A
b (2)where At is the total urban area covered by the chosen case study and Ab is the building footprint. According to its definition in (1)-(2), the SA metrics can only range between 0 and 1 since AS constitutes a portion of Av and, thus, always smaller than Av.
Fig. 1 provides an exemplificative illustration of the portion of accessible void area in a real urban context which corresponds to one of the case studies investigated in this work, i.e., the one labelled Milano MM (see Section 3 for further details on the case study). Fig. 1 compares the amount of accessible void space (in black) and the surface associated with the not accessible space which includes both enclosed urban cavities and buildings (i.e., Ab). The resulting value of SA = 0.56 which means that the 44% of the void space in this urban structure is not freely usable by persons and/or vehicles for moving within the city.
Fig. 1 Visualization of the accessible void area AS, indicated by black
color, in the context of Milano MM case study (see Section 3 for further details on the case study).
2.2 Average Link Length and Normalized Average Link Length
The Average Link Length (ALL) represents the average distance existing between street intersections. This metric can be interpreted as a proxy of the connectivity of the urban matrix [10], which corresponds to easiness of changing routes and finding alternative paths between points lying in the accessible urban areas.
We define the Average Link Length (ALL) as
1 nL i i
L
ALL
nL
(3) 7th Annual International Conference on Architecture and Civil Engineering (ACE 2019)where Li is the length of the ith link (with i= 1,…, nL), defined as the segment of street connecting two intersection, and nL is the number of links identified in the urban structure investigated.
We can visualize the ALL associated with a chosen urban area by displaying a fictitious street network composed of nL links shaped as a regular grid of squared blocks with a side equal to ALL metric. In Fig. 2, we depict this fictitious street network for one of the case studies investigated in this work, i.e., Milano MM (see Section 3 for further details about this case study) where ALL = 55 m.
Fig. 2 Visualization of Milano MM street network assuming that the length of each street link is equal to the ALL measure (i.e., 55 m). The street width is equal to 12 m, computed as the ratio between AS and ALL. The number of
intersections here corresponds to the one observed in the real urban structure (nL).
The quantity ALL is dimensional, it is defined positive but it is not limited by an upper bound. This might lead to some difficulties in interpreting this measure
Then, we introduce a Normalized Average Link Length (ALL_N), which rescales ALL between 0 and 1, as
_
ALLALL
ALL
N
K
(4)where KALL is a priori defined upper bound based on preliminary investigations. We set KALL = 150 m as a representative upper bound for European urban morphologies.
Note that urban areas characterized by deeply different link length distribution may present close ALL_N and ALL values, similarly to all average quantities. For example, peripheral areas, located at the boundaries of the metropolitan area, typically host few but very long links corresponding to extra-urban infrastructures surrounded by extra-urban structures characterized by very short links which were developed in a second moment, after urban expansion. The presence of these
long links may have a strong influence on the ALL_N metric. Then, this metric, after computed, needs to be critically interpreted considering the specific case study under investigation.
2.3 Directness
Directness (D) is a measure of how close is the shortest path following the street network that connects two points located on the border of a considered urban area to their Euclidean distance.
Chosen two points Pi and Pj (with Pi
Pj) on the border of the investigated urban area, the Directness value associated with these points (Dij) is defined asij i j ij
PP
D
SP
(5)where
P P
i j is the Euclidean distance between the points and SPij is the length of the shortest path connecting the two point following the street network. This measure of Directness is generalized for characterizing an urban area as1 1 1 1 B B B B P P i j i j i P P ij i j i
P P
D
SP
(6)where PB is the total number of points located on the border of the urban domain.
According to definition (5)-(6), it is expected that urban structures characterized by a street network shaped as a regular grid presents high D values and the presence of diagonals contributes positively to the Directness measure. On the contrary, the presence of large urban cavities or non-permeable elements such as railways or obstacles deviates linear connections between urban points decreasing the Directness value.
Fig. 3 shows the street network of Milano MM case study (see Section 3 for further details) where each street link width is weighted proportionally to the number of times that is contributing to a shortest path connecting two points on the boundary.
Fig. 3 highlights possible limitations affecting this metric. We observe that the streets which lie on border of the selected area frequently act as shortest path, because Directness is computed considering couples of points laying on the border. This means that the Directness measure might be biased by the chosen shape of the boundaries of the case study, which is subjected to choice of the analyst. Moreover, the evaluation of Directness might encounter some difficulties when concave shapes are considered as there might be the risk to artificially increase the path length with respect to reality by excluding some links external to the selected area.
7th Annual International Conference on Architecture and Civil Engineering (ACE 2019)
Fig. 3 Street network of Milano MM case study (see Section 3 for further details) where each street link width is weighted proportionally to the number of times that is contributing to a shortest path connecting two points on the boundary.
2.4 Tortuosity
Tortuosity is a parameter routinely employed for the characterization of solute mass transport in porous domains. Solute mass dissolved into a fluid undergoes diffusion leading to the progressive dilution of solute concentration forced by the solute concentration gradient. According to Fick’s model [22], the diffusion of a solute in a free fluid can be characterized through a single molecular diffusion coefficient Dm [m2 s-1]. However, in the presence of a porous medium, the diffusion process is limited by the presence of solid boundaries. The effects of the porous spatial structure on the diffusion process are lumped in an effective dimensionless parameter labelled as tortuosity (
[-]). In other words, the tortuosity quantifies, on average, how tortuous is the path of a molecule of solute that diffuses into the fluid phase of a porous sample. The tortuosity ranges between 1, corresponding to a free fluid situation (no solid boundaries), and infinite, corresponding to a medium where transport by diffusion is not possible along a specific direction (i.e., an impermeable or non-percolating geometry). Tortuosity is a geometrical parameter [22], yet analytical quantification of
is possible for simple geometries or, alternatively, empirical correlations have been proposed for estimating tortuosity relying on the void-solid volume ratio (e.g. [23; 24; 25; 26; 27; 28; 29;30]). We rely here on a quantitative method that can lead to a direct numerical estimation of tortuosity from a chosen geometry, upon relying on the implementation of the freely available TauFactor Matlab [31] software [32]. TauFactor numerically computes the diffusive flux (F) of a solute across a two-dimensional porous domain. The solution is obtained applying a unit concentration gradient along a given direction and solving the corresponding diffusion process.A challenge posed by the use of tortuosity as a lumped numerical indicator is that its value is dependent on the direction of transport considered, which implies that the complete characterization of the tortuosity of a bi-dimensional domain is a second rank symmetric tensor [22]. To overcome this element of complexity, we set the x and y-axes to coincide with the North and East directions and evaluate the tortuosity along these directions. Then the trace of the tortuosity tensor (
T) is computed as
T
x
y (7)where
x and
y are the tortuosities computed along the x and y directions, respectively. For simplifying the analysis and the results interpretation and the comparisons provided in Section 4, we introduce the quantity Tor defined as
1
2
T
Tor
(8)The measure Tor embeds both the effects of
x and
yand it is bounded between 0 and 1. The metrics Tor attains a value of 1 when the solid phase is not percolating while Tor =0 corresponds to a porous medium which does not have any impact on the diffusive process. TauFactor estimates the tortuosity by comparing the quantity F against the reference diffusive flux (FH), which would be obtained in a free fluid. Fig. 4 provides an example of the results provided by TauFactor for one of the study case investigated in this work. i.e., Milano MM (see further details about the study case in Section 3). Fig. 4 shows the diffusive flux computed in presence of the solid phase (F), i.e. the buildings of Milano MM, normalized to FH corresponding to the diffusive flux without any solid obstacle. It emerges that the diffusive flux distribution is inhomogeneous and a few pathways are characterized by very high value of , i.e., the diffusive flux in presence of the solid structure is remarkably deviated compared to free fluid system. The tortuosity
y for the case study depicted in Fig. 4 attains a value equal to 2.87, which means that effective diffusion is reduced by a factor 2.87 with respect to a non-porous domain.7th Annual International Conference on Architecture and Civil Engineering (ACE 2019)
Fig. 4 Flux (F) computed for the Milano MM study case (see Section 3 for further details on the study case) normalized over the FH computed in free fluid
in y-direction.
2.5 Constrictivity
The constrictivity parameter β was first introduced by [33] and is computed as 2 min max
r
r
(9)for a single pore with periodic constrictions. In such a simplified geometry, the symbol rmin indicates the radius of the
most constricted area of the pore (the bottleneck), while rmax
refers to the characteristic radius of the bulge. In natural porous media, and similarly in urban structure, a single value of rmin
and rmax is not trivial to identify. To estimate the values of rmin
and rmax in the urban context, we implement the procedure
proposed for porous media by [34]. This procedure identifies rmax as the 50% quantile of the Continuous Pore Size Distribution (c-PSD, for details see [35]) while rmin is the 50% of Pore Size Distribution estimated by simulating mercury intrusion porosimetry (MIP-PSD, for details see [36]). The c-PSD and the MIP-c-PSD are two conceptually different techniques to characterize pore-size distributions that can be seen as the cumulative distribution function of pore sizes in a given porous geometry. The c-PSD determines the portion of total void volume that can be potentially covered by circles of a fixed radius r. On the other hand, the MIP-PSD, fixed the radius r, quantifies the amount of volume of void that can be explored by a circle of radius r starting from a boundary. The MIP-PSD and c-PSD are built by varying the radius r within an opportunely selected range. A detailed explanation of this methodology can be found in [34]. Based on definition of MIP-PSD and c-MIP-PSD, rmin always attains values that are smaller than
rmax. Therefore, the constrictivity parameter is naturally
bounded between 0 and 1: when β tends to 0 this indicates that bottlenecks are predominant features in the geometry and vice versa. We then introduce here the quantity βN
N
1
(10)such as, more intuitively, the higher is the value of βN the more intense is the street constriction effect. To numerically
estimate both MIP-PSD and c-PSD, we employ the freely available software ImageJ/Fiji extended with the free plug-in provided by [37]. To exemplify the computation of the constrictivity metric, Table I. reports the estimates of rmin, rmax
and βN for Milano MM, Milano CS and Milano PM.
TABLE I.VALUES OF rmin, rmax AND CONSTRICTIVITY COMPUTED FOR THREE DIFFERENT STUDIES CASES CONSIDERED IN THESE WORK:MILANO MM, MILANO CS AND MILANO PM.
Urban Structure rmin [m] rmax [m]
NMilano MM 2.1 5.1 0.83
Milano CS 6.8 9.4 0.47
Milano PM 9.4 18.7 0.75
2.6 Topography
Topography has an important impact on street network properties and has a critical role in driving flows of people and vehicles. An aerial view only shows elements projected on a plane, shrinking distances and hiding differences in heights. To keep the same topology of connections respecting link lengths it would be necessary to unroll the ground mesh, obtaining a distorted and trimmed map, not useful for representation or other purposes. The more or less intense inclination of a street affects the connectivity and morphology of the urban space and therefore should be included in the Permeability characterization. To this end, we introduce a specific metric devoted to the characterization of the topography of a urban system
We first characterize each ith link of the investigated study case by estimating its slope (
i) as follows3 ,
arccos
i i D iL
L
(11)where Li is the length of the ith link (i= 1,…, nL) as measured on urban plan while L3D,i is the length of the same link considering a 3D model.
The metric Top is then defined as
1 nL i i
Top
nL K
(12)where Kϕ is a normalization factor included in (12) in order to limit the interval of variability of Top between 0 and 1 which simplifies the metric assessment and interpretation. In this work, we fix Kϕ to 17° which corresponds to a street inclination of 35%, i.e., the highest inclination observed for an urban street (Baldwin Street, Dunedin, New Zealand).
7th Annual International Conference on Architecture and Civil Engineering (ACE 2019)
III. CASE STUDIES
To investigate the ability of the proposed metrics to characterize the Permeability of morphologically different urban areas, we consider nine different case studies. For three Italian cities (Milano, Bergamo and Brescia). The planimentries of the nine case studies are displayed in Fig. 5. Fig.s 5a-c illustrate the three districts chosen for the city of Milano, i.e., Mura Medievali, Città Studi, and Porto di Mare indicated by the labels Milano MM, Milano CS and Milano PM. Fig.s 5d-e report the three districts chosen for the city of Bergamo, i.e., Città Alta, Valtesse and Sentierone indicated by the labels Bergamo CA, Bergamo VA and Bergamo SE. Finally, Fig.s 5g-i display the three districts chosen for the city of Brescia, i.e., Centro Storico, Stazione, and C.se Beretta labelled Brescia CS, Brescia ST and Brescia CB. The same case studies have been investigated in Tadi et al. [4]. These districts are selected because they have developed in three diverse historical phases of city growth and therefore allow assessing the proposed procedure to identify key features associated with specific historical periods. The test cases can be grouped chronologically as follows.
The districts Milano MM, Bergamo CA and Brescia CS correspond to the most ancient part of three cities which were typically delimited by walls during the medieval times and they constitute now the core of the city. The shape of these districts is irregular and the street network is dense and intricate which is a feature commonly observed in those parts of city that were originally developed for pedestrian traffic (i.e., before the broad diffusion of vehicles). In the case of Milano MM (Fig. 5a) and Brescia CS (Fig. 5g) we can observe the tendency of the street network to follow an overall radial configuration which, from the border of the district, conducts to a central major square. The case of Bergamo CA is peculiar because of the influence of the orography of the territory (this urban area lies on the top of a hill).
The districts of Milano CS, Bergamo SE and Brescia ST are modern urban areas which were developed during the cities’ expansion in the 20th Century. These areas are indeed
characterized by a more regular and planned street network and the street width tends to be larger compared to medieval areas.
The areas of Milano PM, Bergamo VA and Brescia CB are the most recent ones among the investigated case studies and are located on the border of the three cities. These are mainly characterised by isolated buildings and wide extra-urban streets (see e.g., Milano PM in Fig. 5c).
The considered study areas differ in dimension, and they range from 50 to 300 ha (see Table II.). The planimetry of the chosen case studies are included in the DBT, Topographic
Database of Lombardy
(http://www.geoportale.regione.lombardia.it/).
Fig. 5 Planimetries of the nine different case studies investigated in this work: (a) Milano Mura Medievali (Milano MM); (b) Milano Città Studi (Milano CS); Milano Porto di Mare (Milano PM); (d) Bergamo Città Alta (Bergamo CA); (e) Bergamo Sentierone (Bergamo SE); (f) Bergamo Valtesse (Bergamo VA); (g) Brescia Centro Storico (Brescia BS); (h) Brescia Stazione (Brescia ST); (i) Brescia C.se Beretta (Brescia CB).
IV. RESULTS AND DISCUSSION
The numerical values of the metrics computed for the nine case studies presented in Section 3 are listed in Table II. The same data are also displayed in Fig. 6 and Fig. 7 by means of radar graphs. Fig. 6 compares different districts belonging to Milano (Fig. 6a), Bergamo (Fig. 6b) and Brescia (Fig. 6c). In Fig. 7, the data are rearranged to compare Permeability results of districts developed in similar historical period: the medieval core (Fig. 7a), the modern areas (Fig. 7b) and the contemporary suburbs (Fig. 7c). The representation via radar diagrams facilitates the contextual reading of all the metrics identifying general trends as a function of the historical development period within the same city (Fig. 6) and site specific features by comparing areas grown in the same historical period but in different cities (Fig. 7).
We can observe that the cities of Milano and Brescia present a similar trend of SA moving from the ancient district (the city cores, i.e., Milano MM and Brescia CE) towards the most recent ones (Milano PM and Brescia CB). This trend express the progressive increment of portion of void space occupied by inaccessible areas to traffic flows, such as countryside and industrial sites, when moving from the city core to the border. This consideration is in agreement with the visual inspection of the maps reported in Fig. 5 and the function of the different city areas. We can also note that, on average, the city of Milano is characterized by higher values of 7th Annual International Conference on Architecture and Civil Engineering (ACE 2019)
