A crucial link in constructing the deep-water foundation of the Huangmao Sea Channel Bridge, a huge steel footing box for the west bearing platform of Tower 5 was hoisted into place June 9.

Guangdong Transport Group says the footing box is 10 m (33 ft) high, weighs 1,500 tons, has double wall spacing of 1 m (3 ft), and covers 1,250 sqm (1/3rd acre). The base is the size of three basketball courts.

Poly Changda Engineering used 71 hydraulic jacks and five hydraulic control pumps to repeatedly press down the steel footing box to a depth of 6.8 m (22 ft), with a 10-cm descent each time.

Steel footing box placed in the sea [Photo by Chen Xinnian / Guanhai App]

Tang Ming, who oversees T5, said the next steps are to pour the bottom concrete and drain seawater to form a large waterless cofferdam to facilitate construction of bearing platforms, pile caps, and towers. To get to this point, he said, the project team overcame the impact of weather, wind, waves, and tides but kept deviation of the central axis to no more than 1.5 cm and an angularity no more than 1/100.

The Huangmao Sea Bridge will have two long spans – the double-span cable-stayed western channel one designed with three pylons and the eastern part with two towers. Reaching over 250 m (820 ft) in height, the five pylons are the most spectacular elements of the complex structure.

By 2024, the Huangmao Sea Channel Bridge will go 31 km (19 miles) from Pingsha Town in the Gaolan Port Economic Zone to Doushan Town in Taishan, Jiangmen. The six-lane structure over 17 bridges will allow for a maximum speed of 100 kmph (62 mph).

The bridge will lead to the Hong Kong-Zhuhai-Macao Bridge in the east, merge into the Guangdong Western Coastal Expressway in the west and continue to the Xintai-Taierzhuang Expressway in Shandong Province. Connections with the Nansha and Humen bridges between Guangzhou and Dongguan and Shenzhen-Zhongshan Corridor sea channel will form a Greater Bay Area cross-sea transport network.