On the influence of pretension and number of geosynthetic layers on piled embankment performance
HARTMANN ; de ALMEIDA ; de ALMEIDA ; BLANC ; THOREL
Type de document
COMMUNICATION AVEC ACTES INTERNATIONAL (ACTI)
Langue
anglais
Auteur
HARTMANN ; de ALMEIDA ; de ALMEIDA ; BLANC ; THOREL
Résumé / Abstract
Soft soil reinforcement with stiff piles is a widespread technique used to reduce the settlements to acceptable levels. A granular embankment transfers the charges above it to the piles, as a result of arching effects. Membrane effect occurs when a geosynthetic is placed under the embankment and above the piles. An experimental system with a mobile tray was developed in IFSTTAR's laboratory in France, in order to investigate the charge transfer mechanism in a granular embankment. Reduced scale models were subjected to acceleration equal to 20 times earth's gravity, in order to simulate the stress states existing in actual embankments. This research aims to determine the influence of the geosynthetic reinforcement in load transfer mechanisms. Various configurations of reinforcements were simulated in the centrifuge. The experimental program also includes the analysis of various charge transfer parameters, such as the geosynthetic pre-tension level, the embankment height, the number of geosynthetics and the rigid pile spacing. The comparative analysis indicated that the inclusion of a reinforcement layer always improves the load transfer, and that an extra layer does not have a significant influence. The pre-tension of the geosynthetic did not present significant influence for the geometry and load conditions studied here.
