14.57 meters diameter "Yongzhou"  TBM successfully completed the first section of Ying'an rock strata inform China news.

Jinsang Underwater Tunnel is 16.18 kilometers long. It is part of 77 kilometer long Ningbo-Zhou Railway from Yinzhou District of Ningbo City to Dinghai District of Zhoushan City. It has design speed of 250 km/hour.

Two TBM one from Ningbo side and another from Zhoushan side bore. Ningbo side is difficult. TBM go first under city and under water. Also this side has most rock formations.

https://m.chinanews.com/wap/detail/cht/zw/10286587.shtml