Prototype-scale field investigation of regulated water-jet pile pressing in dense sand
Prototype-scale field investigation of regulated water-jet pile pressing in dense sand
This paper presents the results of a prototype-scale field investigation of a pile-pressing method enhanced with regulated water jetting for precast reinforced concrete piles in dense sand. The study addresses key challenges in foundation construction for low- and medium-rise buildings and highlights its integration into construction automation. Field experiments performed with an automated pile-pressing machine and various jetting configurations showed that regulated jetting reduced pressing resistance by 55-70 % and enabled penetration up to 1.7 m under the same pressing force of 1834 kN. A mechanistic interpretation of the observed stick-slip effect is proposed as a piston-type hydraulic hypothesis derived from recorded pressing force oscillations during installation. Static load tests indicated that jetting did not compromise axial bearing capacity: settlements under a 700 kN load were 2.2 mm for the control pile and 3.5 mm for the jetted pile, and the allowable load of 466.6 kN satisfied the design safety factor of 1.2. Although the statistical basis of static testing is limited by regulatory requirements, no reduction in axial bearing capacity was observed under the investigated site conditions. Complementary 1-g tests qualitatively demonstrated that regulated jetting with controlled slurry removal mitigates stick-slip behavior. The results provide prototype-scale field evidence of a controllable hydraulic interaction mechanism under real construction constraints.
G. N. Meshcheriakov
11th International Conference on Physical Modelling in Geotechnics (ICPMG2026)
Special Session 1: Physical modelling – from Practice/Industry to Academia
https://doi.org/10.53243/ICPMG2026-73