Pile foundations supporting tall structures must withstand axial and lateral forces, necessitating designs for various horizontal loads such as wind, lateral earth pressure, seismic activity, water waves, ship impacts (at docks), eccentric column loads, cable forces on transmission towers, and more. Consequently, studying the lateral bearing capacity of group pile foundations is crucial. This study investigates pile group lateral bearing capacity behavior utilizing a triangular configuration. Variations in pile spacing within the group foundation include distances of 2.5D and 3D, where wooden piles measuring 400 cm in length and 6 cm in diameter are used, with a pile cap composed of an L-shaped iron profile 45 x 45 x 2 mm affixed atop the group foundation. The soil at the study site, classified as OH according to the Unified Soil Classification System (USCS), consists of organic clay with moderate to high plasticity and an average cone penetration pressure ranging from 5.97 to 6.90 kg/cm2, characterizing it as soft consistency soil. Results from the pile group loading tests indicate an increasing efficiency trend from a spacing distance of 2.5D to 3D. The findings suggest that pile spacing variations significantly impact the lateral bearing capacity of group foundations in soft soil, with implications for the design and construction of tall structures in similar geological conditions.
