Foundation construction is ongoing for SRV’s project Tampere Central Deck and Arena in Finland. This is a unique construction work in Finland; there has never been such an extensive building construction on top of the railway before. At the moment the foundations on the south side of Sori bridge is being built. Construction on the concrete deck will start already next spring 2019. On top of the railway tracks there will be arena for sports and entertainment, casino, hotel and high buildings up to 17 floors opened for public in 2021. In the second phase the north side of the bridge will be built, where there will be high buildings up to 30 floors. This will be opened around 2025.

SSAB has delivered altogether 28 kilometers of steel piles, in total over 4100 tons of steel for the foundations of Tampere Central Deck and Arena. Piling contractor at the site is KFS Finland Oy owned by Kreate Oy and Keller Grundläggning AB. Responsible Site Manager of KFS Finland Oy for the project has been Tünde Lőrinczi. She tells about the project: “The project laid a lot of challenges for the piling works. Working in narrow, hardly accessible areas, close to main roads, existing and underpinned buildings, the police station, especially working close to the railways shows always a challenge, which represents such an important line where delays and shut downs were permitted very limited and rigorously. As ground conditions the project presented a high variety of layers with sudden changes in the bedrock level, which made the planning of the pile lengths quite difficult and considering the relative pile embedment conditions very challenging. The drilling process itself was influenced strongly by the mix of clayey silty, gravel, sandy gravel to boulder moraine soil conditions. Especially the boulder moraine layers represented the biggest challenge while drilling, which did not spare the drilling tools, the steel piles, with the size of the boulders between to 0.5-2.5 m in diameter.”

SSAB’s deliveries have included over 5 200 meters of RD700 piles with 8.0, 12.5, 14.2 and 16.0 wall thicknesses, 4 300 meters of RD800/12.5 and 900 meters of RD600/12.5 piles from SSAB’s Oulainen mill. In addition 11 200 meters of RD320 with 10.0 and 12.5 wall thickness and 5 700 meters of RD220/12.5 have been delivered from SSAB’s Pulkkila mill. Steel piles have been drilled 44 meters deep in the bed rock. Tünde Lőrinczi tells “For the large diameter pile drilling (RD600 up to RD800) the machinery park consisted of two Enteco drilling rigs, type E9090 and E9080. The small diameter piles (RD220 and RD320) were accomplished by two modified excavator rigs, with mounted SPD masts.”

Tünde Lőrinczi has been working in close operation with SSAB since the start of the project. “To carry out such a big project with such a material need and so many different diameters and different lengths, after my opinion is very important to be organized, flexible, fast in acting when changes occur and punctual. To fulfill these requirements of the project SSAB proved to be the appropriate partner”, she says and continues: “The quality of SSAB product never left us unsatisfied during the project. The delivery of the materials on site was sometimes very difficult. Most entrances of the site are directly from heavy frequented roads, where disturbing the traffic was not allowed, with narrow curves and narrow unloading places on site while most of the building area is covered and limited by the tracks, limited possibility is means of machinery and space for unloading the casings which could weigh between 1-6.5 tons and have a length from 12m up to 21.7 meters. Even with so many challenges we had a fast response, solution and remediation which ensured to supply the project with the necessary piles. Customer service and technical support was fast, reliable and helpful.”

“The biggest benefit for me it was the wide range of the products which we were provided from the stock on short notice. Unpredictable changes can always occur especially when the ground is imposing the conditions. The accomplishments of some points and areas were limited by shut down periods, therefore to have the flexibility to adjust and deliver the necessary products was very important”, tells Tünde Lőrinczi. “One challenge, which involves SSAB, it was to ensure the materials for the drilling rigs during the maintenance break period of the Pukkila mill. This meant 6 full trucks with RD320 piles (170 pieces) and 6 full trucks of RD220 piles (240 pieces) delivered and unloaded in one day, with different delivery addresses and planned arrival time for each truck on both entrances in order to not to block the trucks or the traffic in the one way (in and out) narrow entrance of the site. SSAB was a great support in our wish and plan and in the end we managed to carry out the stocking without any disturbance in traffic, other works or delays. I would like to thank all the persons who supported this project together with us, for their efforts” comments Tünde Lőrinczi when the project is about to be finished in October 2018.