Forensic Evaluation of Defective Bored Piles of an Industrial Plant-Paper

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Settlement occurred in pile caps supporting an industrial facility in Haryana before the building’s full load was applied. The affected foundations used 600 mm diameter bored piles designed to extend 16 m below cut-off level. A forensic investigation assessed two piles, Nos. 238 and 239, using geotechnical testing, low-strain pile integrity tests (PIT), parallel seismic testing (PST), and concrete coring.<br /><br />PIT results for both piles showed strong reflections at approximately 3.5–3.6 m, likely associated with a change in pile cross-section near the groundwater table. This prevented reliable assessment of the pile below that depth. PST data were limited for Pile 238, but for Pile 239 indicated an effective pile length of about 13.5 m.<br /><br />Coring provided direct evidence of major defects. In Pile 238, bent reinforcement was recovered at 4.65–5.67 m, and soil was encountered below 5.67 m. The pile was therefore considered bent or broken, or to contain a major discontinuity, at roughly 5–6 m. In Pile 239, concrete cores were generally satisfactory to 9.5 m, but recovery deteriorated below that level. Soil-like material or weak concrete was encountered from about 12.5 m, suggesting poor cleaning of the pile base and an effective length of approximately 12.5–13.5 m, rather than the intended 16 m.<br /><br />The investigation concluded that major construction defects explained the settlement. It also demonstrated the value of combining PIT and PST to identify possible pile discontinuities and length, with coring to confirm their nature and depth.

Keywords

pile settlement

bored piles

forensic investigation

pile integrity test

parallel seismic test

concrete coring

construction defects

geotechnical testing

pile discontinuity

industrial facility foundations