On the afternoon of September 10, accompanied by the rumbling sound of the cutterhead rotating and crushing rock, the first shield tunneling machine independently managed by the Fifth Company of China Railway First Group was successfully launched at the Chao'e Launch Shaft of Qingdao Metro Line 6.

The shield machine launched this time runs from the Chao'e Launch Shaft to Emeishan Road Station, with a length of 723 meters. The geological conditions in this section consist of full-face slightly weathered hard rock and special geology such as unfavorable geological conditions, and it also passes beneath a river bridge and an overpass. In the face of a narrow site and insufficient space, the project department communicated many times with the construction unit, design unit, China Railway headquarters, equipment manufacturers and other parties regarding shield machine selection, cutterhead design, and launch shaft structure adjustment, and ultimately chose split launching for the shield machine.

For the safety of shield construction, the project department organized experts many times to demonstrate the construction plan, optimize the special construction plan and various emergency plans, and conduct targeted emergency drills. At the same time, it carried out advanced geological forecasting and monitoring measurement work, adopted technical measures such as hard rock treatment, and minimized the safety risks of shield tunneling in complex strata to the greatest extent, ensuring the smooth launch of the shield this time.

Since entering the second half of the year, the construction of Line 6 has clearly accelerated. At the end of August, 2 shield machines and 2 TBM boring machines on Line 6 were launched and began tunneling at the same time, entering a new stage of mechanized construction and setting off a new upsurge in construction. It is understood that after two years of research and demonstration, Line 6, on the basis of the preliminary design, increased the burial depth of tunnels across the entire line from 24 meters to 30 meters, raised the mechanization rate of mined tunnel section construction from 61.7% to 91.6%, and plans to invest 31 shield/TBM pieces of equipment, setting a new high for mechanization rate in Qingdao Metro. After the mined tunnel sections adopted the mechanical method, the workforce was reduced from 11,000 to 1,100 people, greatly reducing safety production risks and achieving the goal of replacing people with machinery and reducing personnel through automation.