2017 Prefabrication of Accropode Blocks for Siltation Promotion and Reclamation Project of Yushan in Daishan, Zhoushan

Zhoushan Petrochemical Park Investment Development Co., Ltd. 

The Daiyushan Northern Land Formation Project is located in the waters around the Daxiaoyushan Islands, west of Daishan Island in the northwest part of the Zhoushan Archipelago.

The project included embankment construction, land reclamation backfilling, and foundation treatment. The main works involved the construction of the Wumingzhi–Bianfujiao Seawall, connecting Wumingzhi Island and Daiyushan Island. The Daiyushan Island area has 1,700 m of deep-water shoreline, while the eastern reclamation area added approximately 5,000 m of new deep-water shoreline after reclamation. Both sections adopted rock-fill sloping seawall structures, with foundation treatment using the explosive compaction method to replace soft soil.

Two land formation areas were constructed:

• The sand filling area east of the cofferdam, covering approximately 132,500 m², used hydraulic sand filling combined with quarry stone backfilling. Foundation treatment was carried out using prefabricated vertical drains (PVDs) and surcharge preloading.

• The mud filling area west of the cofferdam and east of the temporary construction road, covering approximately 588,800 m², used hydraulic mud filling, with foundation treatment consisting of both shallow and deep improvement methods.

The total investment of the project was RMB 2.047 billion.

The project involved the prefabrication and installation of more than 100,000 concrete Accropode units in various sizes, including 5 t, 8 t, 10 t, 12 t, and 15 t units, as well as the prefabrication and installation of 30 caissons. The total concrete volume was approximately 300,000 m³, with concrete grades ranging from C30 to C40.

The total construction period lasted 3 years.