On April 19, Fujian Investment Group Putian Pinghai Bay offshore wind farm phase II Project No. 12 fan stand offshore negative pressure bucket installation was successful, which is the world's first successful installation of offshore wind power pile bucket composite foundation.
The negative pressure bucket foundation of No. 12 fan is 25m in diameter and 7m in height, with a total weight of 350t. The negative pressure bucket composite foundation mainly relies on the negative pressure "suction" to sink below the mud surface, effectively improving the horizontal bearing capacity of No. 12 single pile foundation.
In order to complete the pile barrel composite structure of No.12 stand, the offshore wind power company and CCCC third Harbor Engineering Co., Ltd., the project construction unit, have formulated a scientific and reasonable construction scheme, and adopted new technology to carry out the construction of the project. Generally, the principle of "first external, then internal" and "first deep and then shallow" has been followed, and the operation window period has been reasonably arranged, which greatly shortens the working procedure interval. The marine wind power safety monitoring system with independent intellectual property rights independently developed by harbor Institute of CCCC third Harbor Engineering Bureau is adopted for bucket foundation sinking and penetration. The key parameters such as dip angle and penetration depth are monitored in real time throughout the whole process, which provides scientific basis for the smooth construction and ensures the stable sinking of bucket foundation. The pile sinking adopts the information detection system independently developed by CCCC third Harbor Engineering Co., Ltd., which can monitor the shape and sinking speed of the barrel in time to ensure high-quality completion of the task.
The successful installation of pile bucket composite foundation effectively improves the bearing capacity of single pile foundation, which is of great help to the wind power construction of complex geological strata in Fujian sea area. At the same time, it provides a new direction for the design of offshore fan foundation under complex geological conditions.