Guoneng Zhejiang Zhoushan Power Plant Phase III 2×660MW Expansion Project is located in Zhoushan City, Zhejiang Province, invested aby Guoneng Zhejiang Zhoushan Power Generation Co., Ltd. In total, the project has completed the construction of 1,008,735m of drainage board, 23,305m of pipe laying, 161,580m2 of geotextile laying, 107,720 m2 of sealing membrane laying, and 1,106m of sealing trench construction.
Geological conditions within the scope of the construction site of this project are complex, the construction area covers an area of about 52,000 square meters, of which puddles and reservoirs account for about half of the area, and part of the upper part of the area contains large-sized block stones and gravel. In addition, the surface layer of the construction area is soil (0-1) layer of fly ash layer, the thickness is about 1.5 ~ 3.5m, which is loose in nature, and it is not conducive to the stability of the whole sealing system, which is easy to cause leakage phenomenon in the process of vacuum pumping. For the difficulties encountered in the construction process, the project department reasonably arranged the sequence of operation, closed the puddle reservoir in blocks to pump, leasing a large number of steel plates to build temporary construction roads. Before the construction of the drainage board on all soft foundation treatment area, excavators were used to find and remove surface blocks. During the construction process, we ensured that deviations in depth, length, position, etc. comply with the design and relevant specifications. A combination of clay mixing piles and sealing trench is used around the construction area to form a sealing wall. At the same time, high-quality double-layer sealing membranes are used for one-time laying, and a layer of geotextile is laid under the membrane, two layers of geotextile are laid on the membrane, and an 80 cm thick clay medium coarse sand cushion layer is used to protect the sealing membrane, ensuring its integrity. During the construction process of vacuum combined preloading, the vacuum degree of the vacuum pumping system is monitored. After third-party testing, all results meet the design requirements.
This project started on June 21, 2022 and was completed on April 16, 2023, lasting for 10 months. The project quality qualification rate is 100%, and the construction progress meets the overall progress requirements of the owner.