Model Experimental Study on a Method for Evaluating Pile Installation Efficiency Based on the Relationship Between Construction and Resistance Energy Using Dry Toyoura Sand
Model Experimental Study on a Method for Evaluating Pile Installation Efficiency Based on the Relationship Between Construction and Resistance Energy Using Dry Toyoura Sand
Pile foundation construction methods have traditionally been selected based on empirical rules, and an energy-based quantitative evaluation framework remains to be established. A notable bottleneck is the scarcity of model experiments capable of isolating and reproducibly simulating the mechanical processes involved in actual construction. Therefore, this study was aimed at conducting fundamental model experiments to clarify the relationship between lateral resistance and installation energy in pile foundations. All experiments were performed under gravitational (1g) conditions using dry Toyoura sand. Two forms of energy were examined: installation energy required for pile penetration, and resistance energy accumulated in the pilesoil system during lateral loading. Installation energy was calculated as the work done by the press-in machine during installation for piles with different specifications. After installation, monotonic lateral displacement was applied at the pile head, and resistance energy was evaluated as the energy stored in the pilesoil system, obtained from the loaddisplacement relationship. The installation energy increased rapidly with the dimensionless parameter βL, and the energy required to achieve the same penetration depth differed depending on pile type and cross-sectional shape. Although the resistance energy also increased with βL, its increase rate diminished beyond a threshold, and this transition point depended on pile type. Energy efficiency was calculated as the ratio of the installation energy to the resistance energy, and its maximum value was observed at a specific βL value. As this study was conducted under 1g conditions, the stress state may differ from that in actual field construction. Nevertheless, the proposed approach provides a rational, energy-based mechanical framework for evaluating pile construction. Rather than relying on conventional empirical judgement, it offers an experimental foundation for the systematic assessment and comparison of different pile installation methods.
Nana Shinhara; Tomoya Haraguchi; Hidetoshi Nishioka
11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)
Special Session 1: Physical modelling – from Practice/Industry to Academia
https://doi.org/10.53243/ICPMG2026-360