Abstract
Accurate
cadastral maps define legal repositories of land ownership, value and location
by registering and representing land boundaries on a map. These cadastral maps
can be further categorized in various aspects which is depends on the
requirement or the purpose of the user. Infrastructure mapping is such instant.
In this study building up a public road
cadastre system is discussed.
Public
road network in Sri Lanaka has widely spread throughout the country. Until the
present day there is no proper spatial database system to management of the
road system. Accurate road system mapping integrated with spatial database will
provide endless number of advantage from planning development to cost
management of a country. One of the key consideration in planning in the development
based on road network is to understand the current state affairs in the road
network. This requires accumulating reliable, compressive and up-to-date
information on the road network condition that is readily available when
required.
In
my study I am considering the use of road construction
data after completion of the road construction which is the as-built and
design of it. These constructions have completed with international and local
standards imposed by the local government bodies or international funding
projects such as projects from ADB, World Bank etc. So these data obtained can
be justified that they have the required accuracy mentioned above. These data
with its attributes are taken to create a spatial database for a road network
in a sample area. Then this method to be
Proposed
to create a rapid Public road cadastre throughout the country since in
Recent
past almost all the roads have been newly constructed or modified. Through this
standard Road Information System
which also known as RIS could be
obtained where it can be used as a multi-purpose infrastructure.
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Mobility
and transport represent two key components of economic development and human
welfare of a country. Road transport promotes rural development, the transport
and selling of agricultural products, industry and trade, the expansion of
jobs, and access to health, education, and services (Parami Dewi, 2013). The
role of roads is equally decisive at the urban scale, as they connect city
parts and are a framework for the city structure (Sun and Chen, 2000). The
number of reasons for people to travel between two locations has been
increasing and road traffic has become very intense, a trend that will continue
new roads are planned, existing road
networks require daily maintenance, and safety, traffic congestion, and traffic
related air pollution have also to be properly managed. The above requires
inventories/information systems in which roads are properly identified,
classified and described, and where geospatial data, administrative and
technical-functional road features are collected, with the recent development
of different specialist transport-related adding to the need for digital road
data infrastructures to integrate and manage road-related information.
Real-time sensing of traffic and of the road surface to monitor and analyses
road phenomena can ensure a high standard of road performance - including
durability, efficiency and safety - and forecast construction and maintenance
costs.
In many countries both
public and private road inventories have been implemented using databases and
Geographic Information Systems which is called as Road Information System (RIS)
for registering and managing roads. This
is used for the purposes at all stages of a road’s lifecycle such as modeling
the transport demand, road capacity with increasing population, Traffic
congestion, various road forecasting, road’s management and on road’s safety
control, etc.
The Road Cadastre a
name that evokes the concept of road property that is aimed at identifying the
owners who are required to pay for road maintenance. Is a data system,
representing the inventory of every road having public assignment, whose
primary goal is to fix the size of the national roads network. The “Road
Cadastre" introduces the GDF (Geographic Data Files version 3.0. 1995)
European standard in the representation of the road network and the road
related informations which is the most important component required in building
up a road information system.
Unfortunately in Sri
Lanka none of the above is considered in managing or administrating present and
future condition of national road network. Such public road cadaster system is
vital for a development of a country. This paper describes a process of a
creating a rapid road cadaster throughout the country where road construction
data could be found. As a result a road information system can be developed.
For the past ten years
almost all the major road in Sri Lanka has either developed or newly
constructed. All these construction are based on the road surveying. Where
these surveyed data as explained below has been used for the development of
road cadastre.
1.1
Study
area and data
Data
which is obtained has been result of the construction survey of road which can
be list out as
1. Control network establishment.
2. Topographic survey.
3. Setting out Designed Center Line.
4. Cross section and Longitudinal
section Survey
5. Setting out the design cross
section and longitudinal section levels.
6. Final As built topographic survey.
7.
Final
As built cross section survey.
For
this study only the final as built Topographic survey data and as built Cross Section
data are used and it is referenced as construction data.
A
small part of a minor road as in figure 1 has been considered in developing the
road cadaster. This is based on the construction data obtained at the
completion of the road by the respective construction company. Particulars of
the construction data as follows,
In
road construction following procedures are followed in road surveying,
ü As built topography surveyor.
Includes the details about the
centerline of the road, its tar edges and details along the road for a specific
distance in either side.
ü As built cross sections and
longitudinal sections.
Includes all the height of the
center line in specific interval and cross section height in specific interval.
Datum is the mean sea level (MSL).
Figure 1: Study Area
Final
construction data which is the as built data categorized as topographic drawing
and sectional data obtained. In cad drawing both geometry and attribute data
are obtained create feature classes as required in the respective spatial frame
work. Sectional data were used to create a DEM. These two type of vector and
raster layers could be validated through the ground truth data to develop a
standalone Road Cadaster for a particular road network.
3. Analysis
When
considering the construction data following aspect could be found.
As
initial step of any construction is to establish control network which includes
the horizontal as well as the vertical networks.
The
process of establishing horizontal controls which is performed by running a
different zero traverse between the previously established high order reference
points. These reference points were established by differential GPS observation
mode either by the Survey department or by the private sector but private
sector observations and processing should be approved by the Survey Department.
The
process of establishing vertical controls were performed by running a level
line between the permanent BM established by the Survey Department. Both these
networks are approved only when their error has fallen with in the allowable
region. Horizontal control network is in SLD99 Coordinate system while the Mean
Sea Level (MSL) was taken as the datum in vertical control network.
General
construction drawing as shown in figure1
Includes the
center line of the road, tar edge, important point features such as Electric
post, trees and road boundaries
Figure
4: Sectional Drawing
Sectional
drawing as in figure 2 includes the MSL height of the particular section both
side from the center line.
To
build up a road cadaster there should be adequate details to support its
requirement to represent the inventory of every road having public assignment,
whose primary goal is to fix the size of the national roads network
Characteristics
that are required in road cadaster and the possibility of fulfilling the
requirement through the construction data can be discussed in table 1, according
to the
Implementing
Regulation Act in Italy, the European Union Road Federation (ERF) and
regulation of World Bank. (S. Gristina , C. Ellul , A. Scianna, 2016)
Table 1: Comparison between construction
data and road cadastre
Requirements
by the Acts (Regulation Literature Review)
|
Required
by the present lega
l Road Cadastre
|
Fulfillment
with Construction Data
|
Administrative
and Technical road category
|
Yes
|
Yes
|
Speed
limits, Design speed range and speed diagrams
|
No
|
Partially
|
Constructive
elements of road (roadway, shoulder, pavement, etc. with size, position,
spatial relationship)
|
Yes
|
Yes
|
Geometry
of the road axes and Geometrical and traffic features of road sections
|
Partially
|
Partially
|
Road
structures (bridges, tunnels, etc.)
|
Partially
|
Yes
|
Barriers
and lighting elements
|
Yes
|
No
|
Signage
|
No
|
No
|
All
the constructive elements of roads (e.g. Asphalt lanes,Walking path, Parking
area)
|
Partially
|
Yes
|
Equipment
(e.g. Signs, Street lighting, Barriers)
|
Partially
|
Partially
|
Structures
(e.g. Bridges, Tunnels)
|
Partially
|
Yes
|
Historical
data on construction and Use of roads
|
Partially
|
No
|
Elements
related to the management of public transport services, energy, water and
telecommunication (only urban roads)
|
No
|
No
|
Surface
(paved, unpaved)
|
No
|
No
|
Type
of maintenance (routine, periodic, urgent), Work type and Description
|
No
|
No
|
Financial
Unit Cost
|
No
|
No
|
According
to the table 1 it is understandable that the construction data are more than
adequate to the purpose of road cadaster. Addition to the above a Digital
Elevation Model (DEM) could be created where the height of various positions
could be obtained.
4. Result and Discussion
Figure
5: GIS plan overview
Figure
3 represents the overall GIS plan developed by the construction data. Which
represent all point, line and polygon feature for the relevant geometry with
its respective attributes and a raster layer of DEM.
Details
included in the layers will provide many information directly or indirectly
through a query such as
ü
Platform
width and carriage way
ü
Vertical
gradient
ü
Pavement
and shoulder slopes
ü
Horizontal
alignment and etc.
This
GIS plan has been developed in a sample area mentioned earlier. Same method could
be followed in developing many more GIS plan with various road network.
In
recent past almost all the road network had been newly constructed or modified
which means all the construction data available con be developed in above
manner to create a GIS Plan. For better understanding of the output validation
process should be followed for each separate road network.
This
GIS plan can be identified as a standalone cadaster system.
5. Conclusion
Road
construction data are suitable for development of a road cadaster system due to
its accuracy and level of details. The benefits will be minimum when
considering a standalone road cadaster system only for a one network. To
identify this system as a proper Road cadaster system physical model for the
Road Cadastre should consist of a network-based, multi-user, client-server
system, based around a relational database and a GIS, which allows the
representation of the map of the area and the graph of the road network where
optimum use of the road cadaster can be obtained as discussed above.
A
systematic process should be defined to obtain all the available construction
data from different local bodies such as RDA, PRDA etc. and private sector construction
companies where the road constructions data are available.
Engineering & Land Surveyor
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