Road Construction Methods have
changed a lot since the first roads were built in about 4000 BC. Read on to
learn more about road construction methods and procedures.
In ancient times, river
transport was much faster and easier than road transport. The Romans were one
of the first to build stone paved roads in North Africa and Europe to support
their military operations. Later the Arabs built roads that were covered with
tar. The roads were constructed by preparing earthworks and lifting the road
foundation at the center for water
drainage. Road construction techniques gradually improved by the study of road
traffic, stone thickness, road alignment, and slope gradients. Initial road
construction materials were stones that were laid in a regular, compact design,
and covered with smaller stones to produce a solid layer.
The building techniques were
simple but effective as they reduced the travel time considerably and connected
one place to another by land. The Appian Way in Rome still exists although it
was constructed 2300 years ago. If Roman roads are considered the beginning of
road construction, Telford Pavements are known as the second step of this
process, followed by the Macadam Pavements that ultimately lead to the Bitumen
Roads. Today, the concrete roads have added another dimension to stability and
strength of the roadways.
Modern road construction
involves the removal of geographic obstacles, and the use of new construction
materials that are far more improved and durable. Rock and earth is removed by
explosion or digging. Embankments, tunnels, and bridges are constructed, and
then vegetation is removed by deforestation, if necessary. Finally, the
pavement material is laid by using a range of road construction equipment.
Roadways are basically
designed and constructed for use by vehicles and pedestrians. Storm drainage
and ecological considerations should be considered seriously. Sediments and
erosion are controlled to avoid damaging effects. Drainage systems are
constructed so that they should be able to carry waste water to a waterway,
stream, river, or the sea.
Importance
of Earthwork
Earthwork is one of the major
works involved in road construction. This process includes excavation, material
removal, filling, compaction, and construction. Moisture content is controlled,
and compaction is done according to standard design procedures. Normally, rock
explosion at the road bed is not encouraged. While filling a depression to
reach the road level, the original bed is flattened after the removal of the
topsoil. The fill layer is distributed and compacted to the designed
specifications. This procedure is repeated until the compaction desired is
reached. The fill material should not contain organic elements, and possess a
low index of plasticity. Fill material can include gravel and decomposed rocks
of a particular size, but should not consist of huge clay lumps. Sand clay can
be used. The area is considered to be adequately compacted when the roller
movement does not create a noticeable deformation. The road surface finish is
reliant on the economic aspects, and the estimated usage.
Bulldozers are some of the
most important items of equipment used in road construction. Since a bulldozer
is expensive, economic usage factors should be considered when using one.
Bulldozers are extremely useful for road construction where it is possible to
throw the waste excavated material on the road sides. Bulldozers may only be
used if the slopes at the sides are not excessively steep. However, work on
steep slopes can be accomplished by a bulldozer by using special techniques and
expertise.
Construction of roads in
challenging conditions is no more a difficult tasks because the binding agents
and admixtures make it possible for the roads to last long and carry the heavy
loads without cracking under tough environmental conditions. Use of recyclable
materials for the construction of roads has added balance to the enviroment too.
With ever increasing traffic
and exponentially increasing vehicular load, construction management techniques
have become the need of the hour. Managing maximum traffic in optimal space is
what the world needs today. Safe designing of roads, highway space management
and proper drainage of water are major aspects that the site engineers have to
take care of. Construction management includes putting all the pieces of puzzle
together, defining project objectives, dividing the project into modules and
optimizing the available resources. Time, money and resource management are
important aspects. Time saved is money earned, and that is where construction
management techniques are helpful.