Reykjanesbraut Dual Carriageway, IcelandReykjanesbraut Dual Carriageway, Iceland

EFLA, together with sub-consultants, was responsible for the tender design and other consultancies for the project, which involved widening the road from two to four lanes with associated drainage and lighting systems, foot- and cycle paths, extensive noise mitigation, two new footbridges, two new underpasses, widening of a road bridge at the Strandgata junction, and a new junction at Krýsuvíkurvegur.

The aim of the project is to improve traffic flow and traffic safety and provide noise mitigation in this area of heavy traffic. This is the first project that is completed within the scope of the Capital Area Transport Agreement from 2019.

For the most part, EFLA design work took place in 2009 and 2010. To distribute costs, the owner divided the construction works into three parts; an underpass at Suðurholt was built in 2013, the Krýsuvíkurvegur junction in 2017, and most of the road construction and adjoining developments in 2019-2020.

The new Reykjanesbraut motorway is 2+2 lanes with a 3-m central reserve with guardrails, and further guardrails on both sides of the road. To provide noise mitigation, the vertical alignment of the corridor was lowered by up to four meters along Ásland and through Hvaleyrarholt, either side of the junction at Strandgata. Other important noise mitigation measures included new embankments between Reykjanesbraut and Ásbraut at Erluás, embankment top-up at Ásbraut by Álftaás and up to 8-m high steep geocell embankments at Hvammar and Vellir. Plexi-glass noise reduction barriers were built at Suðurhvammur and on the north side of Strandgata junction, and traditional timber made barriers were built along Þúfubarð and at the underpass at Suðurholt.

As part of the project, the bridge over Strandgata was widened to accommodate the additional lanes of traffic. A new underpass for pedestrians and cyclists was also created in this location to allow for expansion of the Strandgata corridor to include the Borgarlínan Bus Rapid Transit system in the future. The new road bridge is a post-tensioned slab in one 20-m span, with the underpass running along its east side abutment.

Two new footbridges were built over Reykjanesbraut, between Hvammar and Ásland at Álftaás, and replacing an underpass which was demolished at Þorlákstún. The footbridges are 46-m long steel arch bridges with wooden floors and stainless steel railings, where the span of the arch itself is 36-m long over Reykjanesbraut. The steel structure for the bridges was assembled in Poland and transported in one piece across the sea and erected in a successful 2020 operation by Ístak, who was the contractor for this part of the project.

The junction at Krýsuvíkurvegur is made of a concrete intersection bridge that accommodates two lanes in each direction. The bridge is a reinforced concrete arch in one 30-m span with retaining walls at the ends. Underneath the bridge, the experience is that of a large dome. The retaining walls are curved in a plane and incline outwards 30° from vertical and thereby form another dome outside the bridge on both sides. The inside of the upper part of the retaining walls is shaped like a concrete roadside barrier. The entire surface of the structure is exposed concrete.

The underpass at Suðurholt is a concrete archway with retaining walls to the ends, a similar shape to the bridge at Krýsuvíkurvegur. The path through the tunnel is 3-m wide. The retaining walls are curved in a plane and the span of the arch is 10 m. The retaining walls slope 30° vertically outwards, forming a dome outside the tunnel on both sides. The upper part of the retaining walls is shaped like a roadside concrete barrier. To the north of the underpass, there are steps and paths to the school district. To the south, the path leads to Vellir. Lava slabs are used as surface finishing along the footpath inside the archway.

The utility companies (HS veitur, Landsnet, Míla and Veitur) were responsible for a preliminary phase of moving installations from the Reykjanesbraut corridor to their final routes outside or to the perimeter of the construction area. EFLA also provided consultancy for a portion of this phase.

The combined construction cost of the whole project is approximately 3,5 billion ISK.

The large increase in traffic capacity on Reykjanesbraut reduces delays in this area of heavy traffic. One of the main goals of the project was to provide traffic noise mitigation in the residential area along Reykjanesbraut, and extensive noise protection is integral to it. Analysis was used to verify the effectiveness of measures.

Traffic safety and the overall quality of footways and cycle paths by Reykjanesbraut are greatly improved with two new footbridges, two underpasses and the adjacent path networks. The bridge at the intersection of Reykjanesbraut and Krýsuvíkurvegur is designed with a view to minimizing material use, where the very economical structural system of a concrete arch is adapted to favourable foundation conditions for that type of structure. In collaboration with Studio Granda Architects attention was paid to the appearance of footbridges and concrete structures with the aim of integrating them with their natural and man-made environs. A new solution was implemented for sound barriers at the Strandgata junction.

• Design management and coordination with third parties
• Consultancy during construction
• Visualisation and presentation for public liaison
• Tender specifications and cost estimation for three tenders
• Road and footway design
• Design of drainage systems
• Road lighting design
• Bridge design
• • Post-tensioned concrete slab
  • New underpass at Strandgata adjoining an existing structure
  • Design of footbridges at Ásbraut og Þorlákstún
  • New archway underpass at Suðurholt
  • New archway road bridge at Krýsuvíkurvegur
  • Design of noise mitigation measures (sound barriers, geocell- and traditional embankments)

• Traffic engineering
• Phasing of construction works

• Improved traffic capacity and traffic safety.
• Improved accessibility and safety for pedestrians and cyclists between districts in Hafnarfjörður.
• Improved acoustics in the residential areas along the Reykjanesbraut corridor.
• The bridge at the junction between Reykjanesbraut and Krýsuvíkurvegur was nominated for the Nordic Bridge Prize on behalf of Iceland in 2019.