Project of Development and Bitumination of Lome Bypass (Phase 2)

Construction of the Project

Construction of the Project

I. Basic information of the project

Lomé is the capital of the Republic of Togo, and the transit trade through the Lomé port is one of the three pillar industries of the country. From the port in the southeast corner of Lomé City to the border between Togo and Ghana, the Road, through the eastern and northern parts of the city in the form of semi-circular, has connected the main national lines in Togo: RN2, RN34, RN1 and RN5. The execution of the project will significantly improve the transport capacity of Lomé Port and promote the domestic economic development in Togo.

Lomé Bypass is designed in accordance with the Class I highway of China with the width of the subgrade 23m, the carriageway 4x3.5m, the width of the hardened verge 2m, and the width of the sidewalk 1.5m. The pavement structure layers from top to bottom consist of the fine grained asphalt concrete of 5cm, the medium grained asphalt concrete of 8cm, the graded broken stone base of 12cm, and the subbase processed with sandy soil and cement of 30cm. The project is also composed of two medium bridges, drainage works, protection works, traffic safety works, and illumination works. The construction of the project is completed in two phases. The second phase is long of 20.7km to Ghana border, currently in the construction phase, the project is expected to be completed in 2019.

II. Key points and difficult points resolved during the construction

The project is located on the verge of the Gulf of Guinea in the south of Togo. The local climate is divided into dry season and rainy season. There are long time sunshine, high temperature and high wind speed in dry season, high precipitation in rainy season. The project passes the alluvial plain and aggraded flood plain, red clay is the most important construction material in the local area, but it’s difficult to reach the standard of compaction degree with normal construction, contraction cracks appear often on the surface of subgrade, which bring hidden troubles to the stability of the subgrade.

In order to solve this problem, the project department carried out a comprehensive sampling of the land along the road, analyzed in detail the factors influencing the earthwork, and determined finally that water content control is the most important factor affecting the quality of construction.

Therefore, the project department considered the water content of red clay as the core, improved the process of different links from site clearing and exploration to spreading materials and compaction on site, finally formed a perfect red clay subgrade construction process in west African region through the repeated analysis of the problem, improvement of process, on site control and summary of achievements.

III. Local employment rate

During the implementation of the project, more than 400 technicians and machinery operators were recruited and trained locally.