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The information system must be structured in such a
way as to offer the following general characteristics:
□ Open architecture
□ Ease of obtaining parameters
□ Data access safety
□ Integrity of data transfer.
The topology of the network is described in terms of
nodes and arcs. Each arc begins and ends in a different
node. The presence of a node in the database is linked
to the following conditions: intersection between one or
more roads, ends between different administrative
authorities ends between different proprietors.
Following the indications of the French Cadastre
obligatory and facultative data can be seen, subdividing
the latter into advised and free data.
It is correct that the solutions adopted are of the “user-
friendly” type favoring the different users (public
administrators, franchise managers, maintenance and
surveillance, police forces, etc.).
The single road can be subdivided into segments,
identified by reference points at the start and finish, a
distance of about 1,000 m however never less than 200
m. These points are geographically referenced and
physically marked on the ground with stones or plates,
and indicated on maps of medium scale (1:25.000 -
1:100.000). In this way all the road information are
referred to the distance along curvilinear abscissa from
the previous reference point.
The SICRE system is predisposed to help the up-dating
of the reference points in relation to changes in the
stretch, re-classification of the road, modifications of the
section, creation of new roads.
Table 3 - Data necessary for the formation of a Road Cadastre.
ADMINISTRATIVE DATA
□
Proprietor and management body
□
Name of the road, start and finish points, and length
□
Territorial data (regional, provincial and communal
territory that the road uses)
□
Limits of the property
□
Pertinence of the company and service
□
Eventual occupancy of the headquarters
□
Ramifications
□
Crossings
□
Intersections
□
Access
FUNCTIONAL AND STRUCTURAL CHARACTERISTICS
□
geometric characteristics of the road: axes, transversal
section, road body and pertinence
□
geometric characteristics and regularity, roughness
and load capacity of the pavement
□
superficial condition;
□
traffic and accidents
□
inventory of works and their condition and functionality
in relation to the laws in force (e.g., anti-seismic
legislation);
□
inventory of auxiliary structures (guard rails, parking
areas, emergency telephones, ...)
□
lateral margins
□
intersections
□
Illumination systems, ventilation (tunnels) and traffic
control systems.
□
Private access
4.1. Experience of ANAS in Italy
The road cadastre that the Italian State Road
Administration (ANAS) is constructing is made up of:
□ A cartographic database of all the national
territory(scale 1:200.000) in order to geographically
localize the information and the various elements;
□ An alphanumeric database containing the detailed
information of the road network and the elements
connected to them;
□ An image bank containing photographs and plans.
For each road the following information is archived:
■ Legal state;
■ Administrative and technical-administrative
ownership;
■ Physical description of the road, other
constructions and competency;
■ Description of the dynamic phenomena, such as
traffic, accidents, etc.;
■ Description of the state of traffic, pollution and
meteorological phenomena.
The data memorized in the databases have been
deduced both by the design and by surveys carried out
on the road (automatic and traditional). In particular in
1995 about 5,000 km of road were studied by automatic
survey (GPS), fixing points at every 20 m on the level
and every 5 m on mountains, and comparing the results
of the survey with topographic data from every 20 km
on the level and every 5 km on mountains.
The elaborated data are seen in the form of thematic
maps that represent the situation of the road network in
reference to a specific problem. They are relative to:
■ Level of safety of the road network-,
