The pile foundation construction of Tianjin Nangang LNG Emergency Reserve Project Receiving Station is located in Tianjin, invested by Beijing Gas Tianjin Group Co., Ltd. The project has completed a total of 16,487m of PHC400 AB 95 pipe piles, 47,605m of PHC500 AB 125 pipe piles, with the length of pipe piles ranging from 27 to 33m, 9,813.42m³ of grouted piles with diameter of 800mm, with the length of piles ranging from 21 to 32m, and 5,686.90m² of composite foundations of rotary spray piles with diameter of 600mm, with the length of piles ranging from 18 to 24m.
The difficulty of this project lies in the condition for stop hammering of PHC piles. The design of friction piles is controlled by the length of the piles, but in the coastal area, after the length of the piles meets the design requirements, the condition for stop hammering can not meet the requirements, therefore, the PHC piles with this kind of problems are solved by "one pile one negotiation" at the site. During the implementation of the project piles, due to the weak backfill stratum and small pile diameter, the rotary drilling rig could not complete the hole drilling operation, and the rotary drilling rig was heavy, and the collapsed hole phenomenon was considered around the hole drilling, for this reason, the hole drilling process was changed, and the drilling equipment was changed to under water rigs.
The project started on April 25, 2021 and concluded on February 28, 2023, and the completion time of each part meets the owner's requirements for construction progress. According to the third party testing, the pile foundation construction meets the design and specification requirements, with a 100% pass rate. During the construction process, we strictly abide by the laws, regulations and rules about civilized construction issued by the country and the owner, and do a good job in civilized construction and environmental protection, so as to meet the requirements of the country, the local government and the owner for civilized construction and the environment. During the construction process, the environmental protection and civilized construction work has been praised by the supervisor and the owner.
