Estudo dos efeitos do LiNO3 na reação Álcali-Sílica e comparação com os efeitos da cinza volante na reação

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Determinação de parâmetros reológicos de argamassas e concreto através de técnicas alternativas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Caracterização dos finos de areia de uma fundição e sua incorporação em argamassa de cimento

Pós-graduação em Engenharia Civil e Ambiental - FEB

Avaliação espaço-temporal da distribuição de fósforo na água e nos sedimentos de fundo das sub-bacias dos rios Cuiabá e São Lourenço e em algumas baias do Pantanal Matogrossense

Pós-graduação em Química - IQ

A BOUNDARY ELEMENT FORMULATION FOR MASONRY WALLS: NON-LINEAR ANALYSIS

In this work, a non-linear Boundary Element Method (BEM) formulation with damage model is extended for numerical simulation of structural masonry walls in 2D stress analysis. The formulation is reoriented to analyse structural masonry, the component materials of which, clay bricks and mortar, are considered as damaged materials. Also considered are the internal variables and cell discretization of the domain. A damage model is used to represent the material behaviour and the domain discretization is also proposed and discussed. The paper presents the numerical parameters of the damage model for the material properties of the masonry components, clay bricks and mortar. Some examples are shown to validate the formulation.

Durabilidade da argamassa mista de revestimento interno contendo dregs-grits em substituição à areia

This paper concerns about the durability of new material in construction. It is noteworthy the fact that increases increasingly searching for alternative materials that do not depend only of natural resources and at the same time be an alternative for reuse of industrial waste. Since the construction materials have a long life and a high cost of civil works and maintenance, it is crucial to estimate the behavior of a new product. Thus , this work discuss the durability of mixed mortar lining , made with waste from the process Kraft pulp production , known as dregs and grits , in partial replacement of sand. Tests were conducted to simulate conditions as adverse environments of constant heat and fire, with the aim of analyzing the behavior of mortar mixed matched the behavior of standard mortar

Caracterização microestrutural e crescimento subcrítico de trincas em cerâmicas odontológicas

Pós-graduação em Odontologia Restauradora - ICT

Estudo das propriedades mecânicas do concreto com adição de cinza de casca de arroz

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Structural characterization of Li-MN doped powders prepared by Pechini's method

Pechini's method has been successfully used to prepare Li-doped MgNb2O6(MN) at short time and low temperature. It consists in the preparation of metal citrate solution, which is polymerized at 250°C to form a high viscous resin. This resin was burned in a box type furnace at 400°C/2h and ground in a mortar. Successive steps of calcination up to 900°C were used to form a crystalline precursor. SEM, DTA and XRD were used to characterize the powders. MN precursor powders containing from 0.1 to 5.0 mol% of LiNbO3 additive was prepared aiming better dielectric properties and microstructural characteristics of the PMN prepared from columbite route. SEM analysis showed that particles increased by sintering, forming large agglomerates. The surface area is also substantially reduced with the increase in additive amount above 1.0 mol%. In XRD pattern of the precursor material with 5.0 mol% of additive was observed the LiNbO3 phase of trigonal structure. XRD data were used for Rietveld refinement and a decrease in microstrain and pronounced increase in crystallite size with the increase of LiNbO3 were observed. It is in agreement with the particle morphologies observed by SEM analysis.

Caracterização e utilização do resíduo de cerâmica vermelha como material pozolânico em matrizes cimentantes

Pós-graduação em Engenharia Civil - FEIS

Recycling residues from the pulp and paper industries in the civil construction

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Estudo sobre o uso de agregados reciclados na composição de concretos e argamassas

Two of the major problems caused by construction activity are the production of construction and demolition waste (CDW) and the exploitation of mineral resources, causing big impacts on the environment. Therefore, the recycling has been shown as an alternative to mitigate the harmful effects of waste on the urban environment and prevent the exploitation of new raw materials. This course work aims to study the behavior of recycled aggregates from Vale do Paraíba in concrete and mortar. Initially, it presents the definitions of recycled aggregates according to CONAMA Resolution No. 307/2002, the aggregate settings for concrete and mortar (such as the grain size, its origin and density, and the characterization parameters according to ABNT), and the definition of ACI method of concrete mix design. Afterwards, it presents the characterization of materials separated by assays. After that, it shows the theoretical concrete proportioning applying the ACI method and experimental concrete proportioning. Then, the analysis of results is performed to finally conclude that the materials provided can't be used to replace natural aggregates because they cannot have the same performance. With the studies, it could be observed that the recycled aggregate presents a great complexity and diversity in origin, therefore the form how the material should be handled requires great care