The piling work for the Kallansillat/Tikkalansaari railroad on Highway 5 between Päiväranta and Vuorela
By Kari Pöllänen, Tommi Lähteinen and Satu Nurminen
 Extensive reconstruction work of the Kallansillat bridges is taking place to the north of the city of Kuopio. The project, which was commissioned by the Road Investments Unit of the Finnish Transport Agency, Liikennevirasto, began in October 2009. In the project, approximately five kilometers of Highway 5 between Päiväranta and Vuorela is being transformed into a motorway, a total of 26 bridges are to be repaired or constructed, along with a service road of some 7 kilometers, some 1.5 kilometers of new railroads, and three interchanges are being built.
The road has been planned for more than 15 years. It will be the main connection road from southern Finland to eastern Finland and the Kainuu region. The part of the road that requires repair, which is used for mixed traffic, has seen many accidents. The current drawbridges are constantly causing problems even when they work properly, as lifting the bridge for the water traffic always stops the road traffic.
The project will be finished by 2014 and will cost €90 million in total. This joint venture has Työyhteenliittymä Kalsium in charge of the main contract. The partners in the venture are Niska & Nyyssönen Oy, Insinööritoimisto Seppo Rantala Oy, and Soraset Yhtiöt Oy. The value of the main contract is approximately €73 million. The contract directly employs some 500 people, of whom at most 150 work on the site at a time. Insinööritoimisto Suunnittelukide Oy is in charge of designing the bridges.
Bridge building requires a strong foundation
Insinööritoimisto Seppo Rantala Oy is a subcontractor for the joint venture with TYL Kalsium. The company is in charge of building the most demanding water and railroad bridges in the project, a total of 13 bridges. The bridge construction work started in February 2010, and the project will be completed in the summer of 2014. The contract sum for the bridge project is approximately €20 million. The Tikkalansaari railroad bridge and the bridges at the Tikkalansaari motorway and service road are the largest bridge projects.
 The Tikkalansaari railroad bridge is the most unique bridge in the project. It was designed by Insinööritoimisto Pontek Oy and commissioned by the orderer of the project, Liikennevirasto. At Tikkalansaari island, the railroad is hoisted hydraulically when necessary, in turn making the headroom for the waterway 12.5 meters. The bridge has a steel lattice structure, and its span is 50 meters. The bridge lattice is prefabricated at the site next to the foundations and then transferred to its place. The transfer distance is approximately 130 meters.
Both pile driving and pile drilling are used in the foundations of the bridge. The piling project has been divided up between several contractors. Four reinforced-concrete underwater coffers, i.e. moulds, function as the foundation for the the bridge. Rock-shoe equipped RR steel pipe piles (D610/S12.5) are used as piles. The installed piles are reinforced and filled with concrete. In the casting, the coffer and the installed piles will form a solid structure.
Concrete-structured pillars of 25.5 meters are built on the coffers to function as the support frame for the drawbridge. The sturdy reinforcements and the more than 700 m3 of concrete required per coffer for the completed structure speaks for the scale of the coffer. A single coffer structure requires 14 to 16 driven piles, their length varying from 24 to 33 meters. The piles are installed at an inclination of 3.5:1. The total bearing capacity of the finished pile group is approximately 5,000 tons, while the bearing capacity of a single pile is 300 tons.
 The bearing capacity is secured with PDA measurements (4 per coffer). The Junttan HHK 4SL hydraulic hammer that is used for the pile driving is equipped with a three-ton extension for the PDA measurements in order to achieve the energy required for the measurements with the existing equipment. If necessary, the machine that is used in the pile driving operations can be equipped with a special Junttan gear to accomplish the final blows. In this case, the mass of the free falling, hydraulically released load is 10,000 kg.
The piles processed with the Junttan PM23 are 16 meters tall at most. The pile extensions are made by welding. The welds are inspected with ultrasonic testing.
“The perfect tool for the job”
The pile driving has proceeded without problems and according to the plan, even though the base conditions for the work vary greatly. Large rocks and terrain conditions that cannot always be discovered in the soil report present a particular challenge. In such circumstances, the professional competence of the all the operators as well as the characteristics and capacity of the machinery used for pile driving are truly put to the test.
 The fact that the work is performed over water makes the job even more challenging – for both workers and machinery. The depth of the water at the installation site is approximately 10 meters, and the work is performed from a temporary bridge founded on steel piles. The bearing stratum for the piles is the rock. The target depth of the piles can be found from the Finnish bedrock underneath the varying layers of mud, sand, clay, and moraine.
The pile-driving foundations for the Tikkalansaari railroad line are made by the Turku-based Kantolan Paalutus Oy. The company uses the Junttan PM23 pile driving rig equipped with the Junttan HHK4 SL hydraulic hammer, acquired in 2001, for the piling work. All in all, Kantolan Paalutus Oy has six Junttan pile driving rigs, of which two are of the PM23 type.
The PM 23 machine that is used at Tikkalansaari has already worked for 10,000 hours without the need for any extraordinary maintenance operations. Harri Inget from Kantolan Paalutus Oy operates the machine. The work of Inget as well as Kantolan Paalutus Oy can be seen in the pile driving foundations of many Finnish bridges. Mikko Rathjens, also a member of the work team, is responsible for the flawless welds in the pile extensions. He also operates as the driver’s partner in the actual piling work. Good communication with the driver combined with extensive experience guarantee a high-quality end result. “The perfect tool for the job,” says driver Harri Inget. He justifies his statement with the good reach, excellent batter piling characteristics and the precise pile control of the Junttan PM23, required e.g. when making pile extensions. Combined with an efficient and reliable hydraulic hammer, these characteristics guarantee that the work runs smoothly and swiftly.
 In addition, the site manager Mika Huhtala from Insinööritoimisto Seppo Rantala Oy, the orderer of the piling job, is satisfied, even though the project has its challenges, such as the demanding soil conditions, logistics, and tight schedules. The new railroad is scheduled to be commissioned already in June 2011, when a train passing should be seen where piling rigs and other machinery now dominate the scene.
The project in numbers
The total amount of structural piles in the entire project is approximately 3.2 kilometers. In the railroad section, there are driven piles for the length of approximately 1 km and drilled piles for 700 meters. The total 5,000,000 square meters of earth to be hauled, of which 1,300,000 square meters is blasted stone quarried from the nearby rock, says something about the scale of the project.
For more information on the project, please contact:
Junttan Oy, Area sales manager Kari Pöllänen
kari.pollanen@junttan.com, tel. +358 50 554 0213 |
