Brasilia, Brazil, 29 March - 3 April 1999
Self-generated Neighbourhood Consolidation in Santiago:
A prototype case study for the social and spatial understanding of large
cities
Bill Hillier, Margarita Greene, Jake Desyllas, Claudio Valensuela, Francois
Dufaux and Pia Rosso
The Bartlett School of Graduate Studies
(Torrington Place Site)
University College London
Gower Street
London WC1E 6BT
England
tel (44) (0)171 391 1739
fax (44) (0)171 813 4363
email b.hillier@ucl.ac.uk
www http://www.spacesyntax.com
This paper reports EU funded research which began with the suspicion amongst
social scientists and architects studying the development over time of
'site and services' settlements in Santiago, Chile, that spatial factors
might be implicated in the very different levels to which settlements
had developed since their foundation in the early nineteen seventies.
From similar origins, some had become well consolidated and seemed to
be thriving, while others remained less consolidated and seemed to have
greater social problems. The aim of the study was to ascertain how far
and in what way spatial factors might have contributed to these differences.
The research combined the expertise of the Universidad Catolica de Chile
in the investigation of social and physical aspects of settlement performance,
with configurational modelling by the Space Syntax Laboratory in UCL.
The theoretical background of the study was the notion of the 'movement
economy' by which spatial structure generates patterns of movement, which
then influence patterns of activity and land uses, with multiplier effects
on both, and on the local grid structure.
The principle techniques used were:
- the construction of indices for settlement consolidation
covering housing, communities and neighbourhoods, and the combination
of all three, together with the design and implementation of a questionnaire
to 553 respondents, and a full survey of 17 settlements;
- the direct observation of the functioning of the
settlements, covering land uses, commercial and social activity, and
pedestrian and vehicular movement;
- the construction of a 'space syntax' computer model
of the whole of Santiago, and radius 1.5 km models for the local areas
of each settlement;
- the construction and analysis of a database comprising
all aspects; and
- the use of space syntax and GIS technique to represent structure and function in the settlements graphically, as an aid to statistical analysis and model building.
The results of the study show that spatial factors,
especially the layout of the settlement and its relation to its urban
context, have played a significant role in the different degrees to which
the settlements have become consolidated. The essential process is one
by which a syntactic property which we call 'local spatial advantage'
(the integration of the settlement within a local area 1.5 km in radius
divided by the mean integration of that area) first generates vehicular
movement adjacent to outward facing edges of the settlement, and this
in turn creates a potential for outward facing commercial activity drawing
on wider potentials than the settlement itself. To the extent that this
potential is realised, we find higher overall levels of commercial activity
in the settlement, and this leads to beneficial effects both on internal
security through higher levels of activity, and on community and housing
consolidation within the settlement. This process is more important in
the development of the settlement than pure income, which can also grow
for reasons which are not settlement related, and with few benefits to
the settlement.
Critical aspects of these results are first that the movement economy
in this case seems to be driven more by vehicular than pedestrian movement,
and that both the consolidation of housing and the long terms development
of the community benefit more from settlement based economic activity
than from straight income levels. The study is offered as a prototype
for the investigation of large cities and their constituent areas.
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