In the current design practice the evaluation of the skin friction developed on piles shaft in sand is obtained using the “beta method”, which accounts, implicitly, for a number of factors, controlling the magnitude of the ultimate shaft friction, tsu, specifically: the initial state of the sand, its modification caused by pile installation, the soil shear strength and the roughness of the pile-soil interface. To analyse the friction interface behaviour, avoiding the effect of the base resistance, a series of 32 pull-out centrifuge tests have been performed, from which the beta coefficients were determined and compared to those estimated from back analysis of loading tests on full scale piles. The beta vs. depth profile gathered from centrifuge tests in dense sand was explained by the increment of the radial stresses on the pile shaft occurred during loading.
Tensile shaft capacity of bored piles in sand from centrifuge modelling
FIORAVANTE, Vincenzo;GUERRA, Lara;
2008
Abstract
In the current design practice the evaluation of the skin friction developed on piles shaft in sand is obtained using the “beta method”, which accounts, implicitly, for a number of factors, controlling the magnitude of the ultimate shaft friction, tsu, specifically: the initial state of the sand, its modification caused by pile installation, the soil shear strength and the roughness of the pile-soil interface. To analyse the friction interface behaviour, avoiding the effect of the base resistance, a series of 32 pull-out centrifuge tests have been performed, from which the beta coefficients were determined and compared to those estimated from back analysis of loading tests on full scale piles. The beta vs. depth profile gathered from centrifuge tests in dense sand was explained by the increment of the radial stresses on the pile shaft occurred during loading.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
