Southern bypass - VINCI Construction Grands Projets

Background

In 1902, French engineer Ferdinand Arnodin designed and built the Newport Transporter Bridge that bestrides the River Usk. This structure was completed in 1906 and is still in use today. It is one of the few transporter bridges in the world that has been maintained in good working order and continues to operate. More than a century after its inauguration, the Newport Southern Distributor Road Project was developed. The project called for the construction of a dual 2-lane carriageway to bypass Newport from the south, providing access to the city’s industrial and port areas. The project included a bridge spanning the River Usk, located a few hundred metres from the old bridge. The Newport City Council decided that the new bridge would be an elegant and elevated structure that reflected the city’s industrial past. For this reason, architect Ron Yee’s bowstring arch design project was selected.

TECHNICAL overview

The project called for the construction of a dual 2-lane carriageway, using existing roads in some sections, and a main 195-metre-long bridge spanning the River Usk, including two long approach viaducts (87 m and 72 m, respectively, with three spans each).
The main bridge is a bowstring arch steel and concrete structure in which the composite deck is suspended from two steel arches. The bridge was launched from both sides of the river, with the two halves resting temporarily on support structures erected in the water (the strong tides made this construction method the only viable option).
From a sustainable development standpoint, the construction of two road sectors represented the project’s key feature. The eastern sector included the widening of an existing road to a dual 2-lane configuration (without interrupting traffic) and construction and renovation of ten existing engineering structures.
In the western sector, consisting of similar structures, specific measures were implemented to protect the environment.
In the second zone, the teams had to build a raised road over a landfill site and, therefore, had to deal with both geotechnical and environmental issues. To prevent future soil compaction in the section where the raised road was not higher than 2 metres, the teams employed the preloading method.

To preserve the environment, the consortium used 95.6% recycled materials for earthworks and roads. This approach earned us the National Champion title at the 2003 Green Apple Awards.

IMPACT

The seaport of Newport had experienced strong growth for many years. We were asked to undertake this project to meet the challenges associated with such growth. The city, which is split in two by the River Usk, has direct access to the Atlantic Ocean.
The structure is also a link, a sort of ring road south of Newport that provides access to industrial zones on the other side of the river.
The structure allows for a shipping channel 152.4 metres wide, providing 7 metres of clearance above the high-water mark of the River Usk. More than 95% recycled materials were used in building the structure, including earthworks and roads. Taking into account its 40-year maintenance component, the project qualifies as a sustainable development initiative.
A southern bypass had been a longstanding need for the city of Newport, both to ease traffic congestion and open up the port and industrial districts. This project showcased VINCI’s aptitude in developing public-private partnerships, particularly in the United Kingdom where the Group enjoys a strong presence through its construction and roadworks subsidiaries.

Project participants

Client
Newport County Borough Council

Project management
Capita Gwent Consultancy

Key figures

Implementation dates
March 2002 to June 2004

Concrete
5,890 m³

Reinforcement
858 t

Earthworks
340,000 m³

M1 Widening Junctions 25 to 28

Nottingham

Découvrir