Jacked Underpasses

The construction of railroad or highway underpasses with the box jacking technology greatly minimizes the interfearance with both trainand vehicular traffic.
The ideas is quite simple: build the concrete monolythic box culvert adjacent to the final position of the works, to the final design elevations, in an excavated jacking trench, on a horizontal sliding slab that acts also as the base for the construction of the box, to then transversally jack the box into the final position with the use of hydraulic jacks.
Working in such a way, the road or railroad that needs to be under passed, is not disturbed at all for the entire duration of the construction of the concrete underpass.
In the case of railrad underpasses, the train traffic is also not disrupted, nor are the tracks removed during the jacking operations, due to the use of the “Verona System” that supports and reinforces the railroad tracks and allows trains to transit at speeds up to 80 km/h.
The main advantages are therefore: assurance of the construction schedule, higher safety and control during the construction of the structure, the elimination of unforeseen events, reduction of the problems caused by having to stop or greatly slow down traffic.
We work in three different types of underpasses: road underpasses, railroad underpasses, and tunnel underpasses.

Road underpasses

These are underpasses that need to be constructed at the intersection of two roads. The traffic is interrupted or deviated for the minimum time required to jack the box in place, usually in the range of 36 to 48 hours.

Railroad underpasses

These are underpassed that need to be built at the interection with a railorad.
The underpass is jacked under the tracks that are previously reinforced and fully supported with the “Verona System”, allowing trains to continue to transit during the jacking operations, at reduced speeds of up to 80km/h.

Tunnel underpasses

These can be either road or railroad underpasses, but with an overburden depth of soil over the top fo the underpass of 4/5 meters or more.
The jacked underpass needs to be fitted with a steel cutting shield that is jacked into the soil allowing the excavation to proceed under the shield before the subsequent push.