The project was located in Jingjiang City, Taizhou City, Jiangyin City and Wuxi City. Our company mainly undertook the construction of six towers Jiangsu Fengcheng - Meili 500kV line Yangtze River crossing section of six base towers of the crossing Yangtze River section of Fengcheng-Meili 500 kV Line. There was a total of 430 engineering piles and 11 trial piles with a total design volume of 21,150.86 m³.
The deepest depth of pile foundation in this project can reach 69 m, and it took about 3 hours to put down the reinforcement cage, which was easy to cause the mud at the bottom of the hole to be sticky or the slag to exceed the standard, and we got a better result by using 15 m³ air compressor for air-lift reverse circulation hole cleaning. During the construction process, because the cage was 6m long, the verticality of the cage was easy to fail to meet the requirements. Through the discussion of the project department, two guiding rulers were used to make 90° angle, and the verticality of the cage was constantly monitored during the cage burial process, which effectively ensured the verticality of the cage, improved the success rate of the cage burial and saved the cage burial time.
The trial pile construction started on May 26, 2020 to June 3, 2020, and the engineering pile construction was from September 30, 2020 to March 24, 2021 and from April 27, 2021 to May 12, 2021. The trial piles were constructed for 9 days and the engineering piles were constructed for 192 days. The 11 trial piles and 430 engineering piles were tested by the laboratory designated by the State Grid Corporation to be Class I piles and were accepted by all three parties.
