In Portugal, the A4 motorway is expected to expand to improve the viability of the area and the city of Porto. Among the various works, expansion, modification and construction of a new tunnel network was also planned. As part of the first phase of the expansion, both the construction of a new 367 m long tunnel and the renewal of the existing tunnels are planned. The new tunnel, located just north of the original tunnel, will have four separate lanes for traffic traveling from Amarante to Porto; the original tunnels will provide the passage for traffic in the opposite direction.
FPT – Fluid Power Technology collaborated on the project by designing and producing the hydraulic equipment suitable for the movement of the formwork used for the construction of the tunnels.
Various wagons were used both to waterproof the entire tunnel and to install the reinforcement. The wagon is equipped with hydraulic equipment to facilitate the installation and handling of the formwork, as well as the lowering, levelling and advancement of the entire structure. And finally, for the concrete casting.
The hydraulic unit built is equipped with both a high-pressure line for lifting operations and a low pressure line for the handling and shifting operations. The hydraulic pump has been designed according to the specific needs of the customer, paying particular attention to the aspect of safety and ease of use. The hydraulic cylinders produced are of various types according to the individual operations to be carried out. At the base of the transport wagon double acting lock nut hydraulic cylinders with FPT mechanical locking ring were used to raise and lower the metal structure. The FPT cylinders were used to lift the formwork, the use of double-acting FPT cylinders made it possible to speed down the lowering operations, guaranteeing the prefect control of the movement of the structure.
The tunnel was completely completed in three months, including assembly and disassembly. This is one of the many projects where FPT hydraulic equipment has been built on specific customer needs.