The renewed Turku Ring Road meets European quality standards

The Turku Ring Road is part of the E18 route and an important corridor both nationally and within Europe. Finland’s last two‑lane section of the route is being upgraded to four lanes, a project that requires, among other things, 13 new bridges. Sweco served as the construction management consultant for Phase 1 of the STk contract.

The Turku Ring Road forms part of the European Union’s E18 route stretching from Scandinavia to the Mediterranean. In Finland, this section is particularly important for port traffic between Turku and Naantali. The upgrade also improves operating conditions for businesses in the region.

“Before the project, the two‑lane section of the E18 on the Turku Ring Road was the last in Finland that did not meet European‑level quality standards,” says Juha Sillanpää from the Finnish Transport Infrastructure Agency, explaining the project background. Expanding the road to four lanes removes a bottleneck in an area where traffic volumes have grown above average. “There is also a high volume of heavy traffic on the ring road.”

A total of 13 new R2‑class bridges are being built in the area. In addition, two bridges were renovated and three demolished. Sweco served as the construction management consultant already in the procurement phase.

A wide round of discussions was also held with potential contractors. “The tendering process was successful. Competition was tight, and we were able to select excellent contractors for the project,” Sillanpää notes.

Recycling aggregates within the project

The construction management consultant’s role continued during blasting operations and bridge construction. The project is divided into two construction phases, which overlapped in summer 2020.

“At the start of Phase 1, the schedule for Phase 2 was still unknown, so defining the scope of the contract was challenging,” Sillanpää says. Most of the aggregate materials for the project were also produced during Phase 1, and the goal was to avoid discarding them and replacing them with purchased materials in Phase 2. “In the end, we stored about 100,000 cubic meters of aggregate for the second phase.”

Special attention was paid to traffic management during construction. “The project involves upgrading an existing road, which has required numerous traffic realignments,” Sillanpää says.

Sweco’s experts also monitor noise protection, landscaping, and environmental values. “For example, new breeding and resting sites were created for flying squirrels in their habitat areas,” Sillanpää explains.

Collaborative development phase led to effective solutions

The project piloted a new STk contract model that included not only design and construction but also a joint development phase. “The client and contractor developed solutions together, enabling many issues to be addressed and resolved already during the planning stage,” says Roope Korpela, Project Engineer at Sweco.

“The development phase worked very well, and the contractor was able to improve the solutions of the road plan,” Sillanpää adds. Thanks to the development phase, cost impacts are monitored throughout the project, and savings achieved through design improvements are shared between the client and the contractor.

Quality control across a large area

The first phase of the project was completed in 2021. “Our tasks included supervising construction work, occupational safety, and traffic safety to ensure that everything proceeded according to plans and the client’s quality requirements,” Korpela says.

“It’s a great advantage that the supervisors are local. You see them almost every day!” Sillanpää adds.

Sweco’s duties continue through the warranty period. “Measurements and monitoring tasks during the warranty period are part of the project’s quality assurance. The contractor is strongly committed to monitoring the structures throughout the warranty period. The road structure is thoroughly measured over the five-year warranty period to detect any potential structural damage. The project’s precise planning and execution have enabled long-term durability of the structures, significantly reducing future maintenance costs,” Korpela explains.