Effects of pedestrianisation on the commercial and ... - Eco-Logica

Measuring urban form
A set <strong>of</strong> comparative spatial indicators
were developed to quantify built
environment characteristics. These
measures all together represent the
physical character <strong>of</strong> a residential
neighbourhood and are assumed to be
relatively independent from each other.
Density was measured using three single
indicators: residential gross density;
employment density and retail density.
The land use entropy index (LUM) is used
as a measure <strong>of</strong> land use mix 2 . Regional
accessibility to workplaces was calculated
using a gravity-based formula. Proximity
indices for shopping centres and schools
were calculated as the median distance
between them and all residential units
within a neighbourhood area weighted by
the number <strong>of</strong> dwelling units. To consider
the permeability <strong>of</strong> each residential
neighbourhood, four different indicators
were developed: the proportion <strong>of</strong> culde-sacs;
street space allocation as a
proportion <strong>of</strong> the total centreline
distances <strong>of</strong> streets in each area; the
route directness index was calculated by
dividing the direct distance between an
origin and destination by the actual
network distance between them and the
average <strong>of</strong> urban block area. The
2
Mean land use entropy was computed as:
s
− ∑ ( pi
) ln( pi
)
i=
1
p
ln( s)
where i is the proportions <strong>of</strong> each <strong>of</strong> the s
land use types which s is the number <strong>of</strong> land
uses. Cervero , R., and K. Kockelman (1997).
"Travel Demand and the 3Ds: Density,
Diversity, and DesignTravel demand and 3D's:
density; diversity and design." Transportation
Research D Vol. 2(No. 3.). The number <strong>of</strong>
seven categories considered for this study:
residential; commercial; recreational;
industrial; governmental; community services
and open spaces.
composite measures <strong>of</strong> the suitability <strong>of</strong>
local streets for walking and cycling: PEF
and CEF - was introduced for this studyrepresent
the quality <strong>of</strong> the built
environment in terms <strong>of</strong> physical activity
options (sidewalks, bike lanes), safety
(low traffic, safe for walking/cycling,
street lighting), and attractiveness
(appearance, building setback, variety in
housing styles, landscape). The values
for these two measures were obtained
through a field observation survey (which
was undertaken for 110 streets). The
percentage <strong>of</strong> neighbourhood area
covered by metropolitan public bus route
buffers was also calculated to consider
the availability <strong>of</strong> public transport
services. The covered area is the area
within 0.2 km <strong>of</strong> local bus routes, where
pedestrian connections to transit areas
are available from the surrounding area.
World Transport Policy & Practice___________________________________________________
Volume 13.1 September 2006
71