SSAB’s Steel Pile Day brought foundation construction professionals to Helsinki, Finland
The 9th Steel Pile Day has been established as an event in which professionals in the field in Finland gather annually. On 21 January 2016, there were again over 300 participants, a third of which were design engineers, a third were contractors and the rest were e.g. authorities and students.
“We wish to be a reliable partner who keeps customer’s business in focus. Furthermore, we aim at exceeding expectations by developing both our own operations and by developing new products for infrastructure construction,” said Hannu Jokiniemi, Director, infra, from SSAB Europe in the event’s opening speech.
For infrastructural construction, SSAB delivers e.g. driven and drilled piles, RD pile walls, combi-walls, safety barrier systems, water mains and pressure pipes for industrial and district heating solutions. Furthermore, SSAB delivers from its Merox company blast furnace slag which is applicable for earth and road construction.
SSAB invests in research and development
Technology Manager Antti Perälä described SSAB’s recent R&D projects. For instance, RRs and RDs piles and RD pile wall manufactured of high-strength steel are results of the company’s product development. Dimensioning software RRPileCalc and PileWallCalc facilitate the design of piles. There are always theses, even doctoral dissertations related to the SSAB infra products under way.
On the Steel Pile Day, students described the results of their theses. Ilkka Isokangas told about his study on the buckling of a point-bearing pile and Rosa Sirén’s thesis was on the tensile capacity of steel pipe piles drilled into rock. Inspecta’s Jussi Kinnunen described his engineer diploma work on the effect of time in the development of geotechnical resistance of a pile.
The program also included interesting examples on recent research projects in Finland. Ramboll’s Outi Kettunen reported on the project of test piling in Jätkäsaari, Helsinki, which studied the effect of compaction and displacement on driveability of different pile types.
Metsä Fibre’s bio-product plant in Äänekoski, Finland
SSAB delivered driven and drilled piles manufactured at the Pukkila plant for the project at Metsä Fibre’s Äänekoski bio-product plant for the total of about 3,500 tons. Drilled piles produced as exact lengths were delivered with a short deadline in July-December 2015. Splice welding of drilled piles were minimized by using exact length, even 26 m long piles. All driven piles were of S550 steel. Thus excellent bearing capacity with smaller costs was achieved.
Ossi Hakanen from Suomen Teräspaalutus Oy and Raimo Isopahkala from Niskasen Maansiirto Oy described the project from the contractors’ viewpoint.
Pasila Tripla in Helsinki
In Pasila, Helsinki, there is a YIT Group’s ongoing project called Pasila Tripla with the value of over €1 billion. In the project, the shopping centre Tripla will be completed next to the Pasila railway station. Later the tower and residential areas will be builded. Construction manager Juha Vunneli from YIT Construction described the project from the building developer’s viewpoint. The construction started by constructing a retaining wall of the parking facility which is implemented by an SSAB RD pile wall.
“We chose the RD pile wall due to its quick and reliable installation methods and reliable water tightness during installation,” said Juha Vunneli.
Petri Tyynelä from Ramboll Finland reported on the project from the designer’s viewpoint. He described how it is possible to ensure the 200-year service life required for the foundation structures and provide the water tightness requirement of 60 l/min for the designed excavation. The dimensions of the excavation in the Pasila railway yard are 230 m x 110 m.
Keski-Suomen Betonirakenne Oy and Fort Ehitus OU installed the RD pile wall. Jouko Pasanen from Ilmi Solutions told about the installation of the piles. The project utilized a new installation method of drilled piles in which the piles were preinstalled by vibrating. At this site, the installation method worked well and the result was a quickly installed wall well within required tolerances.
Pasila Tripla is SSAB’s largest RD pile wall delivery yet
SSAB delivered the total of almost 20 km (about 4,300 tons) of large-diameter RD piles for the Pasila Tripla RD pile wall. The piles were manufactured and equipped at the Oulainen plant from where they were delivered to the work site as ready to be installed elements.
“In a project of this size, good advance planning and communication with the construction site organization are very important. Pile production and delivery capacity must be synchronized with the site schedule. Agreed timetables in both production and deliveries were kept remarkably in this project,” said Business Area Manager Jari Mara from SSAB.
Participants’ comments about the event
Heidi Kekäläinen from Destia Oy attended in the Steel Pile Day for the first time. She works as a site engineer in SVR’s REDI project which also utilizes the SSAB RD pile wall.
“I was particularly interested in hearing the presentation on the Pasila Tripla case because the project is about the same size as REDI in Kalasatama in terms of number of piles. Furthermore, Pasila Tripla is also constructed close to existing ready infrastructure,” said Heidi Kekäläinen.
Kristiina Heikkinen from Junttapojat Oy has attended the Steel Pile Day almost every year. She thinks the event is a good opportunity to meet people in the field and to get to know new products.
“It is always nice to come to this event. The most interesting case this time was the Äänekoski project as a whole , in particular prompt pile design and execution, which also included trial piling," said Kristiina Heikkinen.
Design Manager Tommi Hakanen from Lemminkäinen Infrastructure has also attended the Steel Pile Day almost every year.
“This event as a whole and the possibility to network with the key players in the field are the reasons why I always come to the Steel Pile Day. I make particular use of SSAB’s technical support and SSAB’s design tools which are available on the Internet,” said Tommi Hakanen.