doi:10.3850/GI012

ABSTRACT

Combining with the practical project that makes use of Y-section pile to improve soft clay foundation in Shen-Jia-Hu-Hang expressway, the stress distribution in foundation was studied. The compacting soil pressure and excess pore-water pressure due to pushing in pile cannulation of Y-section pile attenuates rapidly as the distance from pile centre to test point increases. As the pile cannulation goes down, the compacting soil pressure at shallow portion augments firstly, and then minishes; The compacting soil pressure of deep-seated portion increases rapidly when the bottom of pile cannulation reaches, and then becomes big monotonously as the pile cannulation goes down. The compacting soil pressure and excess pore-water pressure due to pushing in pile cannulation augment linearly along with deepness. The accessorial extent of compacting soil pressure becomes small at bottom of pile, and the accessorial extent of excess pore-water pressure hardly becomes. The horizontal earth pressure at rest of sharp-angled point and midpoint of concave arc along pile is different. The horizontal additional stress of sharp-angled point and midpoint of concave arc both augment under embankment load and the undulation is bigger at begin. The most and least horizontal additional stress points of sharp-angled point and midpoint of concave arc along pile appear in different deepness, and the horizontal additional stress of sharp-angled point is bigger than it of midpoint of concave arc at same deepness in certain deepness. The accessorial extent of excess water-pore pressure is bigger at begin. Because the negative friction exists, the fluctuant extent of excess water-pore pressure is bigger from 8m to 20m.

Keywords: Road engineering; stress distribution; field experimental; Y-section pile; compacting soil pressure; excess pore-water pressure; additional stress.

© 2010 by Geotechnical Society of Singapore (GeoSS)