Bang Pakong Combined Cycle (Unit 1-2 Replacement) Project Technical Document Bored pile shall be utilized for pile foundations of the following building/facilities/ equipment: Generation Building, Gas Turbine, Steam Turbine, HRSG & Stack, Central Control Building, Cooling Tower, etc. Only wet process bored pile utilizing polymer sluny or bentonite slurry shall be constructed. The polymer slurry or bentonite slurry used for bored piles shall conform to EIT 1019-46. Bored pile shall be constructed in accordance with EIT 1019-46 standard‘. Vertical reinforcement as well as spiral reinforcement shall be provided throughout the Whole length of pile. The system shall be designed to accommodate any consequences of future settlement and/or differential settlement of the soft material. Filled layers shall not be taken into account for friction resistant of pile. Any adverse effect from negative skin friction shall be taken into consideration. In case the tension piles are required, reinforcing steel dowel bars shall be provided and installed during pile manufacture. The piles shall be designed in such a way that the total settlement, initial settlement and consolidation, shall be limited to 40 mm. The piling shall be suitably reinforced to resist all loadings. The computation of pile capacity shall be calculated from static theory according to subsoil exploration records and design safety factors for all load cases shall be 2.5 for compression and 3.0 for uplift capacity. The pile subjected to lateral load, the maximum bending moment in pile section occurred from lateral load shall not be greater than cracking moment and design safety factor for all load cases shall be 2.0 for lateral load. The pile shall be able to withstanding earthquakes. The determination of the interaction of the entire structure system (structure and pile) with the movement of surroundings soil shall be performed. In the design of pile for machine foundation, which subjected to dynamic loads, the response of the foundation, in the form of modal fi'equencies, deflection, stress, strain, and so on, shall be detennined. Driven piles are allowed for pile foundations of lightweight buildings/facilities/equipment such as trench, duct bank, manhole, etc. All piles utilized in this project shall be new. The foundation system shall be designed and constructed to accomplish the pile installation with no effect to the existing structures from soil movement. The Contractor shall be responsible for all losses and damages occtured from lateral soil moving during pile and foundation construction. The type and size of piles for all stnlctures and equipment foundations shall be proposed to EGAT for approval. Prestressed concrete solid square pile shall conform to TIS 396 Standard. In additional to requirements of TIS 396 standards, effective prestress in piles shall not be less than 4.83 MPa for prestressed concrete solid square pile. Pile splice for driven pile shall be limited to one splice and shall not be in soft soil layer. Splice shall develop adequate strength in compression, tension and moment during installation and in service and be as durable as the pile. The design of pile splice shall be in accordance with ACI code. Splicing detail and calculation sheet shall be submitted to EGAT for approval pn'or to manufacturing the test piles. Volume 2 Page 2A-29