Outstanding infrastructure project with international significance
Second River Niger Bridge in Asaba, Nigeria
Julius Berger was commissioned to eliminate the traffic congestion on the Niger river bridge with a first section of the new southern bypass, while at the same time strengthening the entire region.
The existing bridge over the Niger, built in 1965, connects the cities of Asaba in the Delta state on the western bank and Onitsha in the Anambra state on the eastern bank. It is part of the Trans-African Highway spanning from Lagos to Mombasa in Kenya and is the main east-west connection within Nigeria.
Phase 1, which was commissioned by the Nigerian Federal Ministry of Transportation, includes as highlights: the 1,590-metre reinforced concrete river crossing with maximum spans of 150 meters, a motorway interchange and a toll station. A further challenge was posed by the fact that a total of 10 kilometres of road construction was on extremely soft and swampy terrain. Completion is planned after a 42-month construction period. The team at Julius Berger International, including infrastructure design, structural design, architectural design, work preparation, formwork and scaffolding, geotechnics, materials testing and laboratory as well as procurement, successfully took over the planning of all service phases, including planning coordination with the specialist planners of the river bridge and specific ground improvement.
Three sections are currently being built in parallel using the different production methods of “incremental launching” and “cantilevered construction”: “West Approach” (755 metres, 14 spans, each 55 metres wide), “East Approach” (205 metres, 4 spans) and “Main Bridge” (630 metres, 5 spans with 150 metres width max.). Since the water level of the Niger River varies by about 10 metres between dry and rainy seasons, the foundation work in the river must be planned and coordinated with particular care.
Another challenge our team accepted and successfully overcame: the construction of the road required soil improvement measures in the form of vertical drainage, horizontal dam base reinforcement using geosynthetics and plastic-coated sand columns, known as Geotextile Encased Columns (GEC). These techniques are a way to ensure the load-bearing capacity of the sand dams, which average 6 metres in height, and accelerate the resulting settling.
sand for embankments
Geotextile Encased Columns (GEC)
Design and Engineering
- Concept studies and design concepts
- Approval planning
- Execution and detail planning
- Construction project management
- Quantity survey
- Construction process planning
- Machine concept
- Site facilities concepts
- Formwork and scaffolding planning
- Purchase/procurement of materials
- Value engineering
- Feasibility studies
- Plausibility analyses
- Contract management and management of supplementary requests
- Technical consulting