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The increasing needs of vehicular and pedestrian movement underscore the importance of continually improving our road and rail infrastructure.  But the strive towards developing road and rail networks lends itself to a significant dilemma: how should we manage the intersection between these two networks?

There are two possible solutions to this dilemma: (1) grade separation, and (2) rail crossings.

Where grade separation is prevalent, overpasses allow for the simultaneous flow of cars and trains.  However, often large and expensive structures are required to achieve this that can be difficult to implement in already-congested areas and causes major disruption to movement of traffic during construction phases.


By contrast, underpasses offer a number of advantages over overpasses. They also allow for the simultaneous flow of cars and trains. But they are often smaller, more contact, and easier and less costly to construct in congested areas, with lower global environmental impact.

The new patent-protected Petrucco Technology will allow the Contractor to build underpasses beneath live railway lines whilst minimising the interference between site and rail traffic thus keeping the movement of trains free-flowing during the construction sequence.  This philosophy can also be adopted roads.


The concept involves building a reinforced concrete structure (box) to the side of the railway in order to mitigate any interference with the movement of trains during the construction period.


On completion of the concrete structure, the box is launched using a series of advanced hydraulic jacks and steel spacers resting against a purposely-constructed reinforced concrete "launch slab".

During the jacking operations, excavating to the front face of the box creates the room to allow the box to advance without pushing the soil.  The implementation of innovative anti-drag concepts, including a tapered front, allows the reinforced concrete structure to ease effortlessly through the soil whilst ensuring a safe environment for construction workers to remove surplus spoil from inside the structure.

To support this operation, a patent-protected temporary bridge is built beneath the live railway line or road.  The "temporary bridge" is installed on site without needing to modify the rails, which are themselves supported by inserting transverse beams beneath them.

By isolating the rails from the box jacking activities, the free movement of trains can continue during the construction and installation, thus avoiding delays to the rail network, saving costs and, ultimately, ensuring that network providers are able to continue to deliver a safe, reliable and effective service to the thousands of commuters who rely upon it in their daily lives.

Please take a moment to watch these sample videos....

The VERONA temporary support system installed to allow for free movement of rail traffic during construction of underpass

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