Effect of Second Loading on the Instrumented Continuous Flight Auger Concrete Pile on Porous Soil

Abstract:

This paper presents the results of two load tests carried out in a continuous flight auger pile of 0.4 m in diameter and 12 m in length. The pile was instrumented in depth with strain gages in order to obtain the load capacity along the shaft and the tip. The load tests were carried out at the University of Campinas Experimental Site Test. The subsoil where the pile was installed is constituted by a first stratum of Silty Clay, which is porous and collapsible, of 6.5 m in thickness, followed by a stratum of residual soil of Clayey Silt up to 14 m depth. The first load test was the slow type, and a quick load test in the same pile after five days. From the results obtained with the use of instrumentation, the values for both lateral and tip load were determined in each one of test carried out in the pile studied. With these results and applying the Cambefort’s Law, it was could evaluate the evolution of the shaft friction and tip load in relation to the associated settlements, as well as the occurrence of residual load. The ultimate load obtained in the test was 960 kN and 810 kN for the first and second tests, respectively. The stress for the tip was 853 kPa and 655 kPa for the first and second tests, respectively.

• Periodical: Key Engineering Materials (Volume 753)
• Pages: 285-289
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.753.285
• Online since: August 2017
• Authors: Paulo Jose Rocha Albuquerque*, David de Carvalho
• Keywords: Cambefort Laws, Instrumentation, Load Test, Stiffness Method

References

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