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CONSTRUCTION WORLD
JANUARY
2015
To accommodate the public
utilising this road and provide stra-
tegic crossings for local commu-
nity, there are 10 underpasses for
livestock and pedestrians.
The immediate purpose of this road is
to serve as an access route to the KM III
International Airport from the National
Road MR3, which runs from Manzini to
Simunye. In future this will be the main
corridor link between two borders Oshoek
and Lomahasha, and will link the Swazi
capital city of Mbabane and the Mozambican
city of Maputo.
Background
The Mbadlane Access Road to KMIII Inter-
national Airport commenced operations
in February 2011. At this time the site only
had 25 employees, however by the end of
the year the numbers had elevated to 223
employees who worked 257 730 hours with a
minimum of eight subcontractors.
The contract includes road works and
civil works, the complexity and value has
The project is called ‘D42 –
access road to King Mswati III
International Airport’.
It is a two-lane dual
carriageway which consists
of a total 18 km of asphalt
surfaced road. There are four
concrete motorway bridges
and three structural steel
pedestrian bridges across
the full span of the road.
ROADS AND BRIDGES
>
made it Inyatsi Construction’s (IC) leading
site. One of the unique aspects of the
project is the construction of a free-
flowing interchange which is the first of its
kind in Swaziland.
The project, being a multi-disciplinary
and complex one, has been in the forefront
of career development in the company.
The extensive operations and valued expe-
rience gained on this project has resulted
in the training and development of three
new junior site agents who have since been
promoted to run their own sites. A total of 38
unskilled labourers were grade tested and
hired on permanent basis and are now fully
fledged plant operators and artisans.
Design innovation
Included in the contract is the structural
design of all bridges and drainage structures
and value engineering of the project a whole.
The proposed cross sections comply
with the standards that are currently
adopted by the Ministry of Public Works
and Transport for roads of this type. This
includes the proposed new dual carriageway
from Manzini to Mbadlane, to which this
road will link.
The relatively flat grades in the original
design have resulted in fills as high as 19 m
and cuts as deep as 24 m in some sections.
The proposed 1:1.75 slopes on these cut
and fill banks may result in stainability
problems as some of the locally available
cut/borrow material has very low cohesion.
The proposed road embankment shall have
slopes of 1:2 for cut and fill.
The proposed design also takes cogni-
sance of the fact that the road traffic
volume being served is primarily made up of
passenger vehicles such as busses.
The minimum grade has generally been
increased from 0,5% to 1%. The existing link
to the airport has been constructed at 0,3%,
so the last 5 km of the access road from
the traffic circle has been designed to tie in
with this. The increased grade will improve
drainage characteristics and reduce the
likelihood of elevation offset of stormwater
drains, since these have to be on a grade of
1% to prevent silting.
Technology
Although in Swaziland the construction
industry has been built around brick,
mortar, steel and hard labour, IC recognises
the importance of technology in this field.
As a result the company has introduced new
technologies in the country.
Some of the most recent technologies
in Swaziland that are used for the Mbad-
lana Access Roadsite are the Trimble and
the recycler. The Trimble integrates a wide
range of positioning technologies including
GPS, laser, optical and inertial technologies
with application software, wireless commu-
nications and services to provide complete
commercial solutions. Its integrated solu-
tion allows employees to collect, manage
and analyse information faster and easier
making site operations more productive,
efficient and profitable. Getting the job done
right the first time (which is Inyatsi’s motto)
eliminates rework, saving the company
many costs. Through the use of these tech-
nological improvements: labour, plant,
fuel and supervisory costs are significantly
reduced. However, the greatest saving is on
material, where greater control on the levels
and quantity of materials required results in
reduced wastages. With the Trimble more
time is spent being productive and less time
waiting for surveying and levels checking.
Quality/ISO
The decision to adopt and implement the
King Mswati III International Airport