Within the works for the reconstruction of the SNAM Rete Gas Ravenna-Chieti Methane Pipeline Lot 1, Ravenna-Rimini section having diameter DN650 (26”), the Contractor RTI Sicim – Manna commissioned I.CO.P. to build a trenchless crossing to be carried out with microtunneling technology.

The special work in question involves the sub-bed crossing of the Marecchia River through the
laying of a reinforced concrete pipeline of internal diameter DN2000 and external diameter
DE2500 inside which the pipeline of the methane pipeline will later be housed. The starting point
is located near the village of Santa Giustina in the municipality of Rimini (RN).
The characteristics of the route are as follows:

•  Horizontal straight development;
• Vertical curved development with initial straight section at -7.3% slope, central section with entrance and exit curvature at radius R=2300m and sub-horizontal central connecting section, final straight section at +7.3% slope;
• Total development 750m;
• Cover below the riverbed from about -14 to -16m from the w.p.;

Soils crossed were found to be mostly silty-sandy matrix gravels with a few stretches of silty clay. The average feed rate on the inconsistent soils was 60-65mm/min with reduction to 20-25mm/min on the clayey soils. Average production on a calendar week was 143m per week operating on two shifts. The timing of execution was in line with expectations.