By 1100, Chinese shipbuilders began to implement watertight bulkheads in large junks, a significant technological advancement in maritime engineering. This innovation involved dividing the hulls of ships into compartments, which limited flooding and improved safety during voyages. The use of watertight bulkheads not only enhanced the durability and seaworthiness of ships but also facilitated increased trade and exploration, contributing to the economic prosperity of maritime cultures.

The early use of watertight bulkheads in large junks around 1100 significantly increased maritime safety, inspiring confident maritime verses in East Asian literature. Poets like Li Bai celebrated the adventurous spirit of seafaring in their works, intertwining themes of exploration with the beauty and peril of the ocean.