The works relevant to the Contract concerned the construction of the underground structures need for the execution of the scientific program better know as “Neutrino at Main Injector”.

The project is part of a pure scientific research program aiming to study the “neutrino”, subatomic particles, oscillations, in order to determine if the same have a mass.

The subatomic particles are extracted from an existing accelerator, addressed through magnetic plates to the new underground structure, where their characteristics are defined, before the “neutrino” are “fired” towards Soudan (Minnesota), at a distance of approx. 650km, where their variation compared to the original characteristics are registered.

The main structures concerned by the contract foresaw:

• Unlined excavated tunnel, with length of approx. 1,258m and 6.20m in D. Excavation was made using a Robbins TBM rock shield;
• Positioning in the tunnel of a welded steel made tube with a D. of 1.20m;
• Once completed the tube positioning, backfill was made with low strength type concrete, together with the construction of a lateral crossing along the same tunnel;
• Excavation of two caverns of respectively 8,659 cum. and 5,400 cum.;
• Two access shafts, each respectively of 7m in D. and 38m deep and 8m in D. and 103m deep;
• A connection with the existing laboratory accelerator.

Unfavorable and unforeseen geological conditions have increased the contract initial amount and extended the expected completion date. The Client acknowledged both.

Client: U.R.A. – Universities Research Association Inc.