A recent investigation has uncovered 248 concrete blocks, each weighing approximately 14,000 tons, that were submerged in the sea off the coast of Vietnam. This monumental effort was part of the construction of the Sơn Dương Port, which covers an area of nearly 1,000 hectares and serves the Formosa steel complex in Vung Ang Economic Zone.

The construction of the port took place between 2011 and 2015, with operations commencing in late 2015. According to data from the contractor Samsung C&T, these gravity blocks were essential for the breakwater and dock structures at the Sơn Dương project. The total weight of the submerged blocks amounts to nearly 3.5 million tons, making them a crucial component of this large-scale infrastructure project.

These concrete blocks, often referred to simply as 'concrete blocks,' are actually large hollow reinforced concrete structures designed for stability. Their fabrication was carried out at a large casting yard established on-site, which optimized logistics and construction timelines for the offshore installation process.

The installation of these blocks required high precision and advanced techniques. After being cast using a sliding formwork system, the blocks were launched into the water, towed to their designated coordinates, and gradually submerged to the seabed. Once in position, the hollow interiors of the blocks were filled with sand or stone to maximize their weight, creating a robust gravity structure.

The massive weight of these submerged blocks enables them to withstand the harsh conditions posed by ocean waves and currents, creating a sheltered area for large cargo ships to safely load and unload goods. Currently, Sơn Dương Port is among the largest ports in Vietnam, with a total area of approximately 930 hectares and protected by a breakwater system measuring 5,243 meters in length, allowing for the handling of about 28 million tons of cargo annually.

With its expansive water surface, extensive breakwater stretching over 5 kilometers, and the solid foundation provided by hundreds of these super-heavy concrete blocks, Sơn Dương Port stands as one of the most complex and significant maritime infrastructure projects ever undertaken in Vietnam.