Pile Foundation Response to Ground Vibration from Rock Blasting-Paper

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The study examines how rock blasting affects reinforced-concrete pile foundations and how the slope of the soil–rock interface influences damage. The authors used LS-DYNA to simulate blast-induced ground vibrations acting on a group of two 8 m-long, 600 mm-diameter piles, with the piles socketed 1 m into rock. A coupled smoothed particle hydrodynamics and finite element model represented the explosive and nearby rock, soil, piles, and reinforcement. Three soil–rock interface slope angles were compared.<br /><br />The simulations showed that interface slope significantly changes the propagation of blast waves and the location and severity of pile damage. The leading pile experienced greater deformation and damage than the trailing pile, which was partly shielded by the leading pile. Across all cases, the pile bottoms were especially vulnerable: blast pressure and stresses concentrated there, potentially causing shear failure before the piles reached their plastic moment capacity. The position of the most severe damage also varied with interface slope, occurring nearer the pile top in one case and around the middle in another.<br /><br />The findings indicate that standard vibration limits may not adequately predict pile performance across differing geological conditions. Assessments of structures near blasting should account for the soil–rock interface geometry and the risk of localized pile-bottom shear damage.

Keywords

rock blasting

reinforced concrete piles

pile foundation damage

soil-rock interface slope

blast-induced ground vibrations

LS-DYNA simulation

smoothed particle hydrodynamics

finite element model

pile-bottom shear failure

blast wave propagation