Construction World January 2015

ROADS AND BRIDGES

King Mswati III International Airport

The project is called ‘D42 – access road to King Mswati III

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 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 1% to prevent silting. Technology

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

International Airport’. It is a two-lane dual

To accommodate the public utilising this road and provide stra- tegic crossings for local commu- nity, there are 10 underpasses for and three structural steel pedestrian bridges across the full span of the road. 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 carriageway which consists of a total 18 km of asphalt surfaced road. There are four concrete motorway bridges > livestock and pedestrians.

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CONSTRUCTION WORLD JANUARY 2015