“Bang, bang, bang!” The heavy and powerful impact sound echoes repeatedly at the construction site of Plot D15 on Guoxing Avenue. In the huge deep pit, as machinery rises and falls, 80-meter-long engineering piles are being driven into the ground…… This is the construction site of the South Tower of the future tallest building in Hainan——the 428-meter Haikou Twin Towers. Everyone’s goal is aimed at an important engineering milestone by the end of 2016——reaching the ±0.00 level, which means completing the underground construction of the building and starting to “sprint” towards the 428-meter skyline.
　　Recently, a LOGO solicitation announcement has made the Haikou Twin Towers, a key project in Hainan Province, a social hotspot. Behind the lively activities, the Twin Towers project is proceeding intensively. After a five-year design and demonstration period, this new landmark building of Hainan officially started construction in June 2015. According to the plan, the South Tower of the Twin Towers will complete the foundation pit work by the end of 2016, achieving an important breakthrough in the project milestone.
　　It is understood that the deep foundation pit of the main building of Haikou Twin Towers is not only the deepest foundation pit in Hainan, but also a rare ultra-deep, ultra-large, single-building foundation pit without internal bracing in the world. The deepest part of the foundation reaches 25 meters, and the earthwork volume alone reaches 700,000 cubic meters, comparable to the 800,000 cubic meters of Shanghai Tower, currently the tallest building in China. However, the latter is 632 meters tall, nearly 1.5 times that of Haikou Twin Towers. In contrast, the number of piles for a single tower of Haikou Twin Towers is as many as 1,993, more than twice that of Shanghai Tower, and the bearing capacity of a single pile is twice that of the compressive piles of the main building of Shanghai Tower.