A staff member maintains a device loading immersed tube E23 of Shenzhen-Zhongshan highway underwater tunnel at an immersed tube smart factory of CCCC Fourth Harbour Engineering Co., Ltd. on Niutou Island, Zhuhai, south China's Guangdong Province, Jan. 30, 2023.(Photo: Xinhua)
Staff members prepare the outfitting of immersed tube E23 of Shenzhen-Zhongshan highway underwater tunnel at an immersed tube smart factory of CCCC Fourth Harbour Engineering Co., Ltd. on Niutou Island, Zhuhai, south China's Guangdong Province, Jan. 30, 2023. The prefabrication of E23, the last immersed tube (non-standard tube, including the final joint) of an underwater tunnel, a section of highway linking Shenzhen and Zhongshan in Guangdong, was completed on Tuesday. (Photo: Xinhua)
Staff members prepare the outfitting of immersed tube E23 of Shenzhen-Zhongshan highway underwater tunnel at an immersed tube smart factory of CCCC Fourth Harbour Engineering Co., Ltd. on Niutou Island, Zhuhai, south China's Guangdong Province, Jan. 30, 2023.(Photo: Xinhua)
This aerial photo taken on Jan. 30, 2023 shows immersed tube E23 of Shenzhen-Zhongshan highway underwater tunnel and a vessel for its transport and installation at an immersed tube smart factory of CCCC Fourth Harbour Engineering Co., Ltd. on Niutou Island, Zhuhai, south China's Guangdong Province.(Photo: Xinhua)