Concretes Prepared with High-Density Limestone: Influence on the Transition Zone
E. da Cruz Teixeira, C.M. Medeiros, E.R. da Silva Santos, U.T. Barbosa, N.P. Barbosa
Abstract. The comprehension of the microstructure of concretes provides subsidies and improvement tools of its properties, mainly of durability and mechanical strength. Therefore, this project aims its research to a macro and microstructural analysis in concretes prepared with high-density limestone from the Cariri region of Ceará – Brazil. A comparative analysis with concretes prepared with granite gravel and low-density limestone was performed as a secondary objective. The concretes were prepared using the mix ratio 1:2:2:0.5. For the conventional concrete, granite was used as coarse aggregate and the alternatives concrete were prepared with high and low-density limestone. The test specimens were submitted to the following evaluations: XRD, in order to identify the phases of the constituent materials of the used aggregates; XRF, for the identification of the chemical elements of the aggregates; test of compressive strength of the concretes, the real specific density and SEM of the concrete samples for the analysis of the transition zone. The two types of high density limestones found in the Cariri deposits located in Brazil, presented CaO in their chemical composition predominating in 73% for white limestone and 65% for gray limestone, but the gray type presented in its composition 4.5% silica whereas the white type presented only 1.84%. Concretes prepared with high-density limestone presented an average compressive strength of 16% higher than the conventional concretes. The micrographs obtained in the SEM showed a transition zone with a small number of cracks or fissures and low porosity in the concretes prepared with limestone, in the concretes prepared with granite gravel were found cracks along its interface and accentuated porosity.
Concrete, Limestone, Microestructure
Published online , 9 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: E. da Cruz Teixeira, C.M. Medeiros, E.R. da Silva Santos, U.T. Barbosa, N.P. Barbosa, ‘Concretes Prepared with High-Density Limestone: Influence on the Transition Zone’, Materials Research Proceedings, Vol. 7, pp 45-53, 2018
The article was published as article 6 of the book Non-Conventional Materials and Technologies
 MEHTA, P. K.; MONTEIRO, P. J. M. Concreto: microestrutura, propriedades e materiais. São Paulo: PINI, 2008.
 NEVILLE, A. M. Propriedades do concreto. São Paulo: PINI, 1997.
 FARRAN, J. Contribution minérlogique á I’adhérence entre constituants hidrates dês cimens et lês materiaux enrobés Revue dês materiaux des constrctions, 1956.
 MONTEIRO, P. J. M. Caracterização da microestrutura do concreto: Fases e interfaces; aspectos de durabilidade e de microestrutura. Tese livre docência, Escola Politécnica da Universidade de São Paulo, São Paulo, 1993.
 KAEFER, L. F. BRASIL. Escola politécnica da USP. Considerações sobre a microestrutura do concreto. São Paulo, 2002 (Boletim Técnico).
 RIBEIRO, R. C. C. Utilização do calcário do Cariri cearense como agregado mineral em pavimentação asfáltica. Rio de Janeiro: CETEM, 2006.
 ROSSIGNOLO, J. A. Concreto leve de alto desempenho modificado com SB para pré-fabricados esbeltos: dosagem, produção, propriedades e microestrutura. 2003. Tese (doutorado em Ciências e Engenharia de Materiais), Escola de Engenharia de São Carlos, Universidade de São Paulo, São Carlos.