Experimental Evaluation of Effective Embedment Depth of Press-in Sheet Piling to Mitigate Liquefaction-Induced Foundation Settlements-Paper

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This study used five 1g shake-table tests to assess how deeply press-in sheet piles must extend into a dense, non-liquefiable soil layer to limit liquefaction-induced settlement. A 1/5-scale model contained a shallow foundation over a loose, saturated sand layer, underlain by dense sand. Tests compared a baseline without piles with piles embedded 0, 5, 10, or 20 cm into the dense layer. All tests used the same 0.28g input motion.<br /><br />Sheet piles reduced foundation settlement and altered excess pore-water-pressure behavior. Greater embedment generally reduced peak pore pressure and shortened its dissipation time. Settlement decreased as embedment increased, with a substantial improvement when piles extended 10 cm—half the dense-layer thickness. Settlement reductions at 10 and 20 cm were similar; full embedment reduced settlement by about 72% relative to the baseline. The authors therefore recommend embedding piles at least halfway through the firm layer to provide adequate base fixity.<br /><br />Pile installation also reduced foundation tilting. Transverse (East–West) tilting was fully mitigated at embedments of at least 5 cm, while longitudinal (North–South) tilting was reduced by about 80%. Increasing embedment raised both the magnitude and depth of the piles’ maximum bending moment.<br /><br />The findings indicate that adequate penetration into a firm stratum is important for effective settlement mitigation, though the experiments were conducted at model scale under specific soil and shaking conditions.

Keywords

shake-table tests

liquefaction-induced settlement

sheet piles

foundation settlement

dense sand layer

embedment depth

excess pore-water pressure

shallow foundation

soil liquefaction mitigation

pile bending moment