Banca de DEFESA: MAYSSA ALVES DA SILVA SOUSA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : MAYSSA ALVES DA SILVA SOUSA
DATE: 22/12/2021
TIME: 14:00
LOCAL: Auditório Pós-Graduação em Engenharia Civil on line
TITLE:

Contribution to the Study of Fine-Grained Tropical Soils for Use in Road Paving

KEY WORDS:

Road Pavement. Tropical Soils. Fine-grained soils. MCT. Resilient Modulus. Permanent deformation.

PAGES: 391
BIG AREA: Engenharias
AREA: Engenharia Civil
SUMMARY:

According to data from the National Transport Confederation (CNT), the matrix for the transport of cargo in Brazil shows the country's preference for the road modal, characterizing it as the most representative nationwide. The road network is the most extensive among others in Brazil and due to this great demand for highways, it is common to build new roads or restore old roads and, in both cases, large volumes of materials are used to compose the pavement layers. This fact becomes a bottleneck for projects, since the current traditional soil classification and selection systems for paving (USCS and TRB) basically indicate only granular materials for such use. The road projects carried out in the state of Pernambuco still follow these procedures, which do not fit the reality of Brazilian soils, as they are based on standards developed for temperate soils. Thus, a large part of the soils available in the region are discarded or underutilized. However, over the decades, several researches have indicated the use of fine-grained soils that do not fit within the traditional selection criteria, but that present good mechanical performance. In this research sought to contribute to the evaluation of regional fine-grained tropical soils for use in road paving. For this, an extensive experimental campaign was carried out to analyze the geotechnical behavior of thirteen representative fine-grained soils of the Metropolitan Region of Recife (RMRecife) and a Brazilian Fine Soils Database (BDSF) was set up composed by sixty and seven materials from different regions of Brazil with various geotechnical parameters. The analyzes were conducted under physical, chemical and mineralogical aspects, as well as in the light of pavement mechanics, with the application of specific methodologies, such as MCT (M - miniature; C - compaction; T - tropical) and the Resilient Modulus (MR) and Permanent Deformation (DP) tests, used as a basis for the design of asphalt pavements by the new Brazilian Design Method (MeDiNa). Additionally, basics statistics, correlation, regression and multivariate techniques (Cluster Analysis) were used using Data Science tools to get correlations more completely. The results showed that fine-grained tropical soils (both from RMRecife and BDSF) are materials that present excellent mechanical behavior (high values of MR and low DP), meeting the standards required for a Primary Arterial System. As examples, the soils of RMRecife are mixed materials composed of high percentages of clay and sand, marked by the presence of non-expanding clay minerals, such as kaolinite and illite, with limonite grains in their coarsest fractions, among others characteristics that designate them as lateritic soils, well developed pedologically. In this context, this research contributed to the proposition of several road pavement structures validated by MeDiNa considering different types of materials and traffic levels - proving the technical feasibility of using fine-grained tropical soils, with advantage economic, by reducing costs with transport and acquisition of granular materials. Made application, dissemination and implementation of MeDiNa in the State of Pernambuco and built a database based on criteria of pavement mechanics. Genareted MR prediction equations as a function of the stresses acting on the structure of a pavement subjected to heavy traffic for RMRecife's LA' soils and multiple linear regression models for MR prediction considering specific variables geotechnics.

BANKING MEMBERS:
Externa à Instituição - LIEDI LÉGI BARIANI BERNUCCI - USP
Externo à Instituição - ANTONIO CARLOS RODRIGUES GUIMARAES - IME
Interno - 2767145 - MAURICIO OLIVEIRA DE ANDRADE
Presidente - 1130440 - ROBERTO QUENTAL COUTINHO
Externa à Instituição - VERONICA TEIXEIRA FRANCO CASTELO BRANCO - UFC