Multi-belled cast-in-place concrete piling method has been developed, which use mechanical belling bucket without hydraulic drive. The buckets are designed for several size applicable from medium-rise to super high-rise buildings. Hydraulic belling buckets are also provided as a compatible device for mechanical ones. Field trials were carried out in order to verify the performance of the proposed buckets and the quality of the constructed piles. From the results, it was confirmed that the piles satisfied the required shape and quality by both mechanical and hydraulic belling excavation ways, and that mechanical one could shorten the construction period for compact piles.
