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

PPT Presentation

Pdf Summary

This study evaluated whether press-in sheet piles can reduce earthquake-induced settlement and tilting of shallow foundations on liquefiable soil, and how far the piles should penetrate into an underlying dense, non-liquefiable layer.<br /><br />Researchers conducted scaled shake-table tests using a model foundation and structure. A baseline test without sheet piles was compared with tests in which piles surrounding the foundation either touched the dense layer or extended 5, 10, or 20 cm into it.<br /><br />The sheet piles confined excess pore-water-pressure generation to a narrower zone and helped it dissipate more quickly. They also reduced foundation settlement and tilting. Increasing penetration into the dense layer improved performance, but mitigation with 10 cm of penetration (about half the model dense-layer thickness) was close to that achieved with 20 cm. Transverse tilting was fully mitigated, while longitudinal tilting was reduced by about 80%. Greater penetration also increased both the magnitude and depth of the maximum bending moment in the piles.<br /><br />The results suggest that embedment into the dense layer is important for pile fixity, but that deeper penetration may offer limited additional settlement and tilting reduction beyond an effective depth.

Keywords

sheet piles

liquefaction

shallow foundations

earthquake settlement

foundation tilting

shake-table tests

pore-water pressure

dense layer embedment

pile penetration

structural mitigation