Banca de DEFESA: ANA KARINE SANTOS DANTAS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : ANA KARINE SANTOS DANTAS
DATE: 23/02/2022
TIME: 14:00
LOCAL: Auditório Pós-Graduação em Engenharia Civil on line
TITLE:

Geological-Geotechnical Characterization and Analysis of Pile Settlement Estimation in an Unsaturated Soil

KEY WORDS:

Settlement, estimation, retroanalysis, static load test

PAGES: 160
BIG AREA: Engenharias
AREA: Engenharia Civil
SUMMARY:

João Pessoa, in the last decades, has experienced a significant process of verticalization. Vigorous buildings create the urban landscape of the city, requiring knowledge of the ground where their foundations will be laid, as well as the behavior of the foundation system (structural element and soil). In the design of pile foundations, safety is defined emphasizing only the ultimate bearing capacity, and the behavior of the structures is evidenced by settlements and deformations. In the study area of the present work, a multifamily residential building will be implanted, with excavated piles as the foundation. This work aims to characterize the soil and evaluate the settlement estimation of one of these piles, analyzed in isolation, using established calculation methods. The research program and geological-geotechnical characterization presented here aims to contribute to the knowledge of the city's subsoil, which is located on the Barreiras Formation, as well as providing parameters for the estimation of settlement. The investigation campaign covers percussion soundings and the collection of deformed and undisturbed samples for laboratory tests, which were carried out at the Soil Laboratory of the Federal University of Pernambuco. The physical characterization consisted of granulometric analysis, consistency limits, and real grain density. In addition, double edometric tests, direct shear tests in natural and flooded conditions, and triaxial CID tests were performed. The characteristic curve was also obtained using the filter paper technique (Whatman No. 42 paper), adjusted by Van Genuchten, with quantification of the matric suction in the drying and wetting paths. In this way, it was possible to evaluate the influence of suction variation on soil parameters, especially on Young's modulus. To understand the behavior of an isolated pile, in terms of the settlement, the methods of Aoki (1979, 1984), Poulos and Davis (1980), and Randolph & Wroth (1978) were used to estimate the settlement suffered by an isolated pile. of the excavated type. The results were compared with values obtained experimentally through static load test (SCP) since one of the best ways to know the behavior of the pile-soil system is through Static load test (SCP). 3 PCEs were carried out in piles of the work, whose settlements presented were less than 10% of the pile diameter, which made it impossible to extrapolate the curve to obtain the breaking load. Through the PCE retroanalysis, Young's modulus of the soil used in the settlement estimation was determined. Regarding the geotechnical characterization, the differences in strength and deformability promoted by saturation were observed in this study when comparing the tests under natural and flooded conditions. The tested soil revealed an intermediate behavior between sand and clay, for which the Randolph-Worth method was most proximate to the settlement valuesmeasured in the load test. From the analyzes carried out, it was also possible to observe that the soil deformation parameters represented the point of greatest uncertainty and influence on the variation of the estimation results.

BANKING MEMBERS:
Externo à Instituição - BERNADETE RAGONI DANZIGER - UERJ
Presidente - 1130440 - ROBERTO QUENTAL COUTINHO
Externo à Instituição - WILSON CARTAXO SOARES - UNIPÊ