29 July 2020, 12:24
The S7 Expressway crosses Poland from Lubień to Rabka Zdrój, north to south, passing through the Voividato Malopolskie region. There are three separate sections currently under construction. One of these sections goes through Luboń Maly Mountain, for which a tunnel with two separate tubes is being built, with a total length of over 4 km. This phase has proven to be the most time-consuming and costly of the entire Expressway project. There are two independent tubes, approximately 2 km each, designed for traffic to flow in a single direction. The tunnel will feature two emergency passageways between the tubes, a ventilation room, as well as technical and service installations. In order to build it, 1922.40 m have been perforated for the left-hand tunnel, and 1919.60 m for the right.
Excavation began on the north side of the right-hand tube in March of 2017, and the entire tunnel is expected to be finished mid-2021.
ULMA’s Engineering Team designed an MK Formwork Carriage 15.50 m wide and 10.70 m long to pour the mine tunnel. With a single unit made from standard MK pieces, the carriage was able to adapt effortlessly to the tunnel’s complex geometry. For the roof, a special panel was designed to be load-bearing during the pour and permit easy stripping without the need for hydraulic systems. TMK Formwork Panels provided an excellent finish. The carriage boasts a high load-bearing capacity, working platforms, access stairways, and other integrated safety features.
For this project, ULMA provided the support of our Engineering Teams, as well as technical and assembly support. Due to the excavation clearance, the characteristics of the project and the variety of tasks that had to be performed simultaneously, the complete assembly of the carriage has been carried out in sections pre-assembled on the outside and moved inside the tunnel tubes.
After pouring each 6.25m section, the carriage was easily advanced with a hydraulic system that facilitated formwork placement and stripping, lowering, and levelling, as well as advance.
The success of this project demonstrates how collaboration with the client from the outset guarantees success, even in the face of demanding deadlines.