Each year the American technical journal, Engineering News-Record published by McGraw-Hill, nominates a man of the year in the construction field. In 1990, Prof. Pietro Lunardi was included as one of those who had contributed with his ideas to the achievement of significant progress in the construction field, "he invented the 'Cellular arch technique' to excavate wide span underground caverns in cohesion-less ground".
This original construction system can be employed to drive bored tunnels with very shallow overburdens up to a diameter of 60 m. in very poor ground without causing surface subsidence.
One significant application of this system was for the construction of the Venezia Station on the Milan Urban Link Line. A cavern 30 m. in diameter and 270 m. in length was bore tunnel excavated right in the centre of the city with an overburden of only 4 metres and under the water table.