China Railway's 15.01-meter shield machine "Fenfa" rolls off the production line

en.Wedoany.com Reported - On October 20, the 15.01-meter super-large-diameter slurry shield machine "Fenfa," jointly developed by China Railway No. 3 Engineering Group and China Railway Hi-Tech Industry Corporation's China Railway Engineering Equipment Group under China Railway, rolled off the production line in Jiangmen, Guangdong. The equipment will be used for the left-line tunnel construction of the Fudong Road river-crossing passage in Wenzhou, Zhejiang, and will work together with the "Qiangcheng" shield machine responsible for right-line excavation on the Oujiang River crossing project. The "Fenfa" has an overall length of approximately 121 meters and was specially designed for shallow cover, high water pressure and complex stratum conditions. On-site excavation has not yet begun.

The Wenzhou Fudong Road river-crossing passage has a total length of 3,065 meters, including a 1,950-meter section crossing the Oujiang River, and is constructed using the shield tunneling method. The tunnel must pass beneath the Meiyuan anchorage, the main navigation channel of the Oujiang River and the flood control embankment, with a minimum cover thickness of only 9.3 meters at the launch section. The project will implement an ultra-shallow cover launch on the riverside tidal flat, with the left and right lines planned to use two shield machines for synchronous excavation in the same direction.

To adapt to the river-crossing construction conditions, the "Fenfa" adopts a slurry balance design with an excavation diameter of 15.01 meters. Its chamber can withstand approximately 60 tonnes of pressure per square meter and can adapt to soft strata, small-radius curves and large longitudinal slopes. The equipment integrates advanced geological prediction, stratum interface identification and gas environment monitoring systems for identifying formation changes ahead and monitoring the tunnel construction environment.

The cutterhead is equipped with wear-resistant blocks and wear-resistant protective layers, as well as an online tool wear monitoring system. To address the risk of tunnel segment flotation, the development team installed a laser positioning system and displacement inclination sensors at the shield tail to adjust grouting pressure and installation accuracy by monitoring changes in segment position. The equipment also features reprogrammed control programs for 28 thrust jacks, which can adjust thrust force according to geological conditions and correct the shield attitude in real time.

The Wenzhou Fudong Road river-crossing passage is Wenzhou's first cross-river municipal tunnel and Zhejiang Province's first tunnel project crossing an anchorage area. Upon completion, the project will connect the north and south banks of the Oujiang River and form a cross-river transportation corridor from downtown Wenzhou to Wenzhou North Railway Station.