Formulação de misturas betuminosas a quente : contribuição para um novo método de formulação
Miniatura indisponível
Data
2013
Título da revista
ISSN da revista
Título do Volume
Editora
Resumo
O interesse do presente estudo prende-se com o facto das características
mecânicas duma mistura betuminosa serem influenciadas pelo tipo de compactação
utilizado no estudo de formulação.
Deste modo, pretende-se contribuir para o desenvolvimento do método de
formulação de misturas betuminosas fabricadas a quente, simulando as condições de
compactação em obra.
O principal desafio do presente estudo foi o de comparar a tradicional formulação
pelo método Marshall com uma proposta de formulação utilizando o compactador de rolo,
baseada no desempenho mecânico das misturas betuminosas.
A formulação laboratorial adequada deverá incorporar um equilíbrio das
propriedades relacionadas com o desempenho, para selecionar os componentes duma
mistura específica a aplicar em obra.
Mais do que determinar a composição ótima duma mistura betuminosa, um método
de formulação baseado no desempenho, procura avaliar e assegurar níveis adequados das
características mecânicas duma mistura betuminosa em serviço.
Foram determinadas experimentalmente as propriedades relacionadas com o
desempenho das misturas estudadas como, módulo de deformabilidade, fendilhamento por
fadiga e deformação permanente.
Neste estudo propõe-se um novo método de formulação baseado no desempenho,
como alterativa viável ao método Marshall, mostrando as suas vantagens, após validação do
método por comparação das característica obtidas em provetes compactados em laboratório
e colhidas em obra.
The main purpose of this study is related to the fact that mechanical characteristics of a bituminous mixture are influenced by the type of compaction used in the study of mix design. Thus, this study intends to contribute to the development of methodologies for design of hot mixed asphalt, simulating in situ compaction conditions. The major challenge of this study was the comparison between the traditional mix design according to the Marshall method and a proposed mix design using a new compaction procedure, the roller compactor, based on the mechanical performance of asphalt mixtures. A proper laboratory mix design should integrate a balanced consideration of the asphalt mixture performance related properties, in order to select the components of a specific asphalt mixture to be applied. Rather than determining an optimal composition of an asphalt mixture, a performance-based mix design method, seeks to assess and guarantee proper mechanical characteristics of an asphalt mixture during service condition. Performance-based characteristics of the studied asphalt mixtures, such as deformability modulus, fatigue and permanent deformation behaviour were experimentally determined in laboratory A new mix design method, based on performance, is proposed in this study, as a feasible alternative to the Marshall method. The proposed method and its main advantages were validated by comparing performance related characteristics of in situ collected samples and laboratory produced samples.
The main purpose of this study is related to the fact that mechanical characteristics of a bituminous mixture are influenced by the type of compaction used in the study of mix design. Thus, this study intends to contribute to the development of methodologies for design of hot mixed asphalt, simulating in situ compaction conditions. The major challenge of this study was the comparison between the traditional mix design according to the Marshall method and a proposed mix design using a new compaction procedure, the roller compactor, based on the mechanical performance of asphalt mixtures. A proper laboratory mix design should integrate a balanced consideration of the asphalt mixture performance related properties, in order to select the components of a specific asphalt mixture to be applied. Rather than determining an optimal composition of an asphalt mixture, a performance-based mix design method, seeks to assess and guarantee proper mechanical characteristics of an asphalt mixture during service condition. Performance-based characteristics of the studied asphalt mixtures, such as deformability modulus, fatigue and permanent deformation behaviour were experimentally determined in laboratory A new mix design method, based on performance, is proposed in this study, as a feasible alternative to the Marshall method. The proposed method and its main advantages were validated by comparing performance related characteristics of in situ collected samples and laboratory produced samples.
Descrição
Orientação: Ana Cristina Freire ; co-orientação: Luís Quaresma
Palavras-chave
ENGENHARIA CIVIL, CIVIL ENGINEERING, MISTURAS BETUMINOSAS, BITUMINOUS MIXTURES, COMPACTADOR DE ROLO, ROLLER COMPACTOR, REVESTIMENTOS DE PAVIMENTOS, FLOORING MATERIALS, MATERIAIS DE CONSTRUÇÃO, BUILDING MATERIALS, MESTRADO EM ENGENHARIA CIVIL