For the first time, the Horseshoe‑shaped TBM is used to bore tunnels for roads and railways in the mountain area.The cutterhead is 10.95m high and 11.90m wide.The Horseshoe‑shaped TBM differs from the traditional circular machines not only in the section but also in its construction method.When the machine is applied to soft soil tunnelling through mountains, the tunnel space utilization will be increased by 20% to 30% in comparison to circular cutting.The Horseshoe‑shaped machine will bore a 3,345m tunnel with a maximum overburden of 81.05m.The machine started boring on the 29th of December 2016.On the 7th of November 2018, the Baicheng Tunnel Project of Menghua Railway was awarded the “ITA Technical Project Innovation of the Year 2018”.