masterThesis
Avaliação de instalação e desempenho em terreno arenoso de uma estaca helicoidal instrumentada
Fecha
2018-07-31Registro en:
QUEIROZ, Felipy Lima de. Avaliação de instalação e desempenho em terreno arenoso de uma estaca helicoidal instrumentada. 2018. 85f. Dissertação (Mestrado em Engenharia Civil) - Centro de Tecnologia, Universidade Federal do Rio Grande do Norte, Natal, 2018.
Autor
Queiroz, Felipy Lima de
Resumen
Helical piles are foundation types used to support compressive, tensile, or lateral
loading. The capability of being loaded right after installation, the high production rate
and the possibility of reutilization in different projects are a few advantages of helical
piles. Despite the increasing use of helical pipes, the amount of data collected from
field experiments with instrumented helical piles is still relatively small. In this work, the
tensile behavior of an instrumented helical pile embedded in a sandy soil deposit is
evaluated along the effect of disturbance caused in the ground after installation. The
three-plate pile used in this investigation was instrumented with electric resistance
strain gages attached to five distinct sections along its shaft. Two sections were used
for measuring torque and the other three sections were used for measuring axial load.
The performance of the instrumented pile was monitored during installation by
measurements of the installation torque. The axial load in the instrumented sections
was monitored during two static pullout tests. The disturbance caused by pile
installation was evaluated with the results of tests with a dynamic cone penetrometer
(DCP) and by radargram renderings from a ground penetration radar (GPR). Results
from the instrumented sections showed that the contribution of the top helical plate in
the overall bearing capacity is smaller than that of the intermediate and bottom plates.
Results from the DCP and the GPR devices suggest that the passage of the helical
plates during pile installation reduced soil compaction within a zone of influence from
the shaft of approximately three times the diameter of the largest plate.