Recently, the dual-mode shield machine mode conversion commissioning and acceptance for the right line of the Huangmabu Station to Shiyan Center Station section (referred to as the "Huang-Shi section") of the Shenzhen-Daya Bay Intercity Railway was successfully completed, marking the successful completion of the shield machine's transition from split to integral configuration and its first excavation mode conversion.

The Huang-Shi section has a total length of 7.837 kilometers and features long-distance hard rock, upper-soft lower-hard strata, and soft soil strata, with extremely complex geological conditions that a single excavation mode of the shield machine cannot satisfy the construction requirements. Based on actual site conditions, the project team deployed four "EPB + TBM" dual-mode shield machines, launching from the working shaft of the Huang-Shi section and being lifted out at Huangmabu Station and Shiyan Center Station respectively. When entering long-distance ultra-hard rock strata, the shield machines can switch to TBM mode for excavation, requiring a total of 16 mode conversions during the process.

The shield machine that completed its first mode conversion was launched in EPB mode, entered full-face hard rock at ring 46, and at ring 57 simultaneously underwent the transition from split to integral configuration and mode conversion, switching to TBM mode to continue excavation. In this mode, the machine achieves high rotation speed and fast excavation efficiency; compared with the traditional mining method of "soft ground with soft mode, hard ground with hard mode," the dual-mode excavation speed will be 3 to 5 times faster. This mode conversion took 18 days to complete, accumulating rich experience for the preparation work, process coordination, and handling of details for subsequent shield machine mode conversions.