China’s first tunnel boring machine exported to Italy – a CREG 699 10.03m diameter TBM designed and manufactured by CREG (China Railway Engineering Equipment Group Co., Ltd.) – has broken through successfully on the first drive of Italy’s twin-bore Lonato Tunnel on September 15, 2022, after excavating 4.8km.
The tunnel lies along the Milan-Verona high-speed railway link on the Brescia- Verona section placed in northern Italy and is being built by the Cepav Due Joint Venture. Containing two tunnel boring machine drives, the Lonato Tunnel is totally 9.6km long with an alignment that passes mostly via sandy gravel and clayey silt strata.
Considering this difficult geology, CREG has provided the 10.03m diameter EPBM with a customized double screw conveyor design. With two muck discharge modes including a single screw conveyor mode and a double screw conveyor mode, the adaptability of the machine in high water pressures and alluvium with an exceedingly high content of very large boulders is improved, guaranteeing the building safety and tunneling efficiency.
Despite the impacts of the COVID-19 pandemic and the difficult geological conditions, the machine has achieved a good performance rate with a max daily advance of 28m and a max monthly advance of 504m since its launch in March 2021.
The Milan-Verona high-speed railway link is a chief strategic infrastructure project for plus being part of TEN-T (the Trans-European Transport Network) Mediterranean high-speed rail corridor linking the western and eastern regions of Europe via Italy, France, Spain, Slovenia and Hungary.