Concreto autoadensável: fundamentos, tecnologia, viabilidade técnica e econômica
Data
2023-01-25
Autores
Calesco, Murillo Adalberto Figueiró
Título da Revista
ISSN da Revista
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Editor
Universidade Estadual Paulista (Unesp)
Resumo
A utilização do concreto autoadensável como alternativa ao concreto convencional vibrado tem sido amplamente investigada por se mostrar promissora, no que se refere às propriedades físicas e mecânicas tanto no estado fresco como endurecido. Para ser considerado autoadensável, um concreto deve possuir três propriedades fundamentais: fluidez, habilidade passante e resistência à segregação. A aplicação do material em obras correntes é benéfica, já que o material é capaz de se adensar apenas com seu peso próprio, dispensando a compactação manual, logo, reduzindo a mão de obra necessária. Além disso, seu uso é altamente indicado em obras que contém estruturas aparentes, formas estruturalmente complexas, esbeltas e/ou com elevadas taxas de armadura, já que evita o aparecimento de nichos de concretagem e trazem um acabamento melhor à estrutura. Mesmo considerando os fatores citados, seu uso ainda é pouco disseminado por ser uma tecnologia nova e ainda com muito potencial de desenvolvimento, além de que os métodos de dosagem são relativamente diferentes dos concretos convencionais, o que também leva a um aumento do custo do metro cúbico do concreto se analisado individualmente. Contudo, os custos estimados com mão de obra direta, indireta e outros custos indiretos tendem a diminuir. Diante das circunstâncias, foi realizado um trabalho de pesquisa sobre a tecnologia do concreto autoadensável, sua compreensão no meio técnico brasileiro e internacional, apontando suas vantagens econômicas, tecnológicas e ambientais.
The use of self-compacting concrete as an alternative to conventional vibrated concrete has been widely investigated for showing promise in what refer to fresh and hardened, physical and mechanical properties. To be considered self-compacting, a concrete must have three fundamental properties: fluidity, passing ability, and resistance to segregation. The application of the material in current works is beneficial as the material is able to densify only with its own weight, dispensing with manual compaction, thus reducing the necessary labor. Furthermore, its use is highly recommended in works that contain exposed structures, structurally complex, slenderness, and/or with high armor rates, as it avoids the emergence of concrete failures and brings better finishing to the structure. Even considering the aforementioned factors, its use is still little disseminated as it is a new technology and still with much potential for development, in addition to the fact that the dosage methods are relatively different from conventional concretes, which also leads to an increase in the cost of the cubic meter of concrete if analyzed individually. However, the estimated costs with direct labor, indirect and other indirect costs tend to decrease. Given the circumstances, it is presented a research work on self-compacting concrete technology, its understanding in the Brazilian and international technical environment, pointing out its economic, technological and environmental advantages
The use of self-compacting concrete as an alternative to conventional vibrated concrete has been widely investigated for showing promise in what refer to fresh and hardened, physical and mechanical properties. To be considered self-compacting, a concrete must have three fundamental properties: fluidity, passing ability, and resistance to segregation. The application of the material in current works is beneficial as the material is able to densify only with its own weight, dispensing with manual compaction, thus reducing the necessary labor. Furthermore, its use is highly recommended in works that contain exposed structures, structurally complex, slenderness, and/or with high armor rates, as it avoids the emergence of concrete failures and brings better finishing to the structure. Even considering the aforementioned factors, its use is still little disseminated as it is a new technology and still with much potential for development, in addition to the fact that the dosage methods are relatively different from conventional concretes, which also leads to an increase in the cost of the cubic meter of concrete if analyzed individually. However, the estimated costs with direct labor, indirect and other indirect costs tend to decrease. Given the circumstances, it is presented a research work on self-compacting concrete technology, its understanding in the Brazilian and international technical environment, pointing out its economic, technological and environmental advantages
Descrição
Palavras-chave
Concreto Autoadensável, Tecnologia do Concreto, Viabilidade técnica, Self-compacting concrete, Concrete technology, Technical viability