A dream of Lahti
A 50-year old dream, the relocation of Highway 12 out of central Lahti has begun.
There are plenty of tried and tested Destia partners working on the Lahti construction site. The principle is clear: no extended sub-contracting chains are allowed, and Destia partners may only have one further level of sub-contracting partners.
The volume of the base rock excavation will be 600,000 to 700,000 cubic metres. A similar amount of other land masses will be moved. Just the Soramäki junction excavation site is a sight to behold.
The excavated rock material will be used for the structural parts of the road construction. As progress is made with the laying of a foundation for the road surface, a crushing station will be established onsite. The quality of the base rock has been surveyed at several locations to ensure that it is suitable for crushing and using as material.
Parts of the road will be laid on a solid rock foundation, but others will run through softer terrain. Preliminary paling has revealed that the paling work required will be extensive.
What makes the nearly nine-kilometre long construction project different from traditional road construction is that there are quite a few bridges along the way, requiring extensive earth work. Most of 2018 will be spent on laying down and reinforcing the challenging foundation. The lanes are planned for completion by the end of next year. The year after should see the completion of road surfacing, lighting and finishing touches.
For the most part, the section of the road constructed by Destia will have 1+1 lanes. During the Summer, the speed limit will be 100 km/h. The section of the motorway under construction will have three multiple level junctions and eighteen bridges, the longest of which are the 220-metre Vähäjoki bridge and the 270-metre Luhdanjoki bridge. The smallest bridge will be the underpass constructed as a migratory route for otters – due to its structure, this too is considered a bridge.
The motorway will also become a part of a special freight network, which means that it will have to accommodate the transport of objects larger than 7x7 metres in size.
The longer bridges, including the two over 200-metre long ones, have been designed by A-Insinöörit and Swecon. The smaller bridges have been designed in-house by Destia. Destia’s own geo planning expertise has been applied to the geo planning in the project. Additionally, Destia’s expertise on railway tracks is required, as one of the longer bridges will span across the Kouvola–Riihimäki railway line.