Banca de DEFESA: Heitor Cardoso Bernardes

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : Heitor Cardoso Bernardes
DATE: 24/01/2023
TIME: 14:00
LOCAL: Online-Teams
TITLE:

Analysis of the Behavior of a Piled Raft Based on Columns and Foundation Instrumentation

KEY WORDS:

• Piled raft; Geotechnical instrumentation; tall building; soil-superstructure interaction.

PAGES: 240
BIG AREA: Engenharias
AREA: Engenharia Civil
SUMMARY:

The lack of scientific papers involving the monitoring of loads, stresses and strains in the foundations of structures built on tropical soils is one of the limiting factors to the application of advanced techniques to the design of piled rafts as foundations of tall buildings in Brazilian soil. The present paper aims to understand the geotechnical behavior of a large piled raft using the monitoring of strains in the building’s columns and piles, the stresses at the raft-soil interface, and the foundation settlements. The thesis stands out from other related studies as it is the first Brazilian case contemplating this level of instrumentation of a high-rise building. As specific objectives, it is listed: the analysis of the load distribution between the piles of the group; the mobilization of stresses at the raft-soil contact; the mobilization of the lateral side friction of the piles along its depth; and the influence of the interactions between the foundation elements in the aforementioned topics. Field and laboratory tests were performed on-site, and associated with axisymmetric and three-dimensional finite element analysis to aid in the assessment of the measured data. The monitoring of pile strains suggests the occurrence of soil expansion, caused by the raft excavation process, up to approximately 6 months after the excavation was completed. The presence of different soil profiles under the raft, with different mechanical properties, affected the distribution of the foundation settlements and the pile loads. The measurements recorded by the total stress cells indicated that the mobilization of the resistance at the raft-soil interface was superior to the values predicted in the design phase. The effect of the superstructure stiffness contributed to successive load redistributions on the instrumented columns, which caused a uniformity in the foundation settlements and reduced the load difference between the piles positioned in different soil profiles.

BANKING MEMBERS:
Externo à Instituição - ALEXANDRE DUARTE GUSMAO
Externa à Instituição - BERNADETE RAGONI DANZIGR - UFRJ
Interno - 2517970 - GREGORIO LUIS SILVA ARAUJO
Interno - 2161425 - JUAN FELIX RODRIGUEZ REBOLLEDO
Presidente - 1122864 - RENATO PINTO DA CUNHA