Banca de DEFESA: Clayton Henrique Dalla Cort do Nascimento

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : Clayton Henrique Dalla Cort do Nascimento
DATE: 05/07/2024
TIME: 09:00
LOCAL: Sala Teams (On-line)
TITLE:

"Dynamic Parameters for CAPWAP Analyses in Continuous Flight Auger Piles"

KEY WORDS:

Load test, CAPWAP, PDA, CFA pile

PAGES: 145
BIG AREA: Engenharias
AREA: Engenharia Civil
SUBÁREA: Geotécnica
SUMMARY:

Load testing is the primary means of mitigating uncertainties in deep foundation geotechnical projects. In this regard, dynamic load testing (DLT) is a highly attractive solution as it allows for rapid results with lower financial costs compared to static load testing. DLT is interpreted through CAPWAP analyses, which utilize signal matching techniques between field readings and those obtained from a pile-soil model. This technique involves trial and error, and interpreting the results requires good judgment from the engineer conducting the analyses and inputting the soil and pile parameters into the model. The most important parameters in the analysis are the shaft quake (qs) and damping factor (Js), which are commonly assumed to be constant along the pile shaft, regardless of soil stratigraphy (variation in soil type and mechanical properties). In other words, CAPWAP analyses in this approach become highly dependent on experience and subjectivity.
The aim was to establish correlations between the undrained shear strength (Su) and the qs and Js of the soil along the shaft of continuous flight auger (CFA) piles. It also aimed to correlate qs and Js with the penetration resistance index (N). To achieve this, Vane Shear Tests (VST) and Standard Penetration Tests (SPT) were conducted, along with a static load test and two dynamic load tests on piles at a construction site in Sinop, Mato Grosso, Brazil. The soil in the city has an alluvial origin and consists of poorly consolidated sediments. The terrain at the site comprises cohesive soil up to a depth of 15 meters (inorganic clay), transitioning to cohesionless soil (silty gravel, sandy silt and sand) down to a depth of 32 meters (limit of the boreholes). The groundwater table was observed at a depth of 2 meters.
The results of the tests were analyzed, and some correlations between soil properties and the qs and Js parameters obtained from the CAPWAP analyses were observed. Within the limitations of the analyses conducted, it was concluded that the CAPWAP model parameters are indeed not constant throughout the depth and vary according to the type and mechanical properties of the soil. It was found that most of the results diverged from those expected in the literature, possibly due to the different soil properties in Sinop, Mato Grosso, and the type of pile analyzed (CFA).

COMMITTEE MEMBERS:
Externa à Instituição - SILVANA BLUMEN FOA
Interno - 2161425 - JUAN FELIX RODRIGUEZ REBOLLEDO
Interno - 3132829 - RAFAEL CERQUEIRA SILVA
Presidente - 1122864 - RENATO PINTO DA CUNHA