1200mm Dia Bored Cast-in-situ Pile Foundation Design for Highway Bridge

This detailed structural drawing depicts the design and reinforcement details of 1200mm diameter bored cast-in-situ piles for a highway bridge foundation. The drawing includes comprehensive reinforcement arrangements with main bars (32-9 nos. and 25-18 nos.), spiral reinforcement (Φ16@100mm c/c and Φ16@1500mm c/c), and stiffener bars (Φ12@150mm c/c). The pile is designed for M40 grade concrete with Fe500D reinforcement steel. Key structural parameters include a working vertical load capacity of 397.6T (normal), 466.9T (seismic), and 466.2T (wind) with 9.4T horizontal load. The pile extends approximately 32m from cut-off level with reinforcement curtailment at 23.5m depth. The drawing provides multiple cross-sections showing reinforcement placement, anchorage details for spiral stirrups, and vertical bar lapping specifications. A 6mm thick steel liner is indicated at the upper portion of the pile with 75mm concrete cover requirements. The foundation is designed for severe exposure conditions in seismic zone IV, with detailed notes covering lap lengths, anchorage requirements, and construction methodologies.