Concrete aggregates properties crushed by jaw and impact secondary crushing

Autor(es)

Ulsen, Carina ^[1] ; Tseng, Ester ^[2] ; Angulo, Sergio Cirelli ^[3] ; Landmann, Mirko ^[4] ; Contessotto, Renato ^[1] ; Balbo, Jose Tadeu ^[2] ; Kahn, Henrique ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Polytech Sch, Min & Petr Engn Dept, Sao Paulo - Brazil

^[2] Univ Sao Paulo, Polytech Sch, Transportat Engn Dept, Sao Paulo - Brazil

^[3] Univ Sao Paulo, Polytech Sch, Construct Engn Dept, Sao Paulo - Brazil

^[4] IAB Weimar gGmbH, Weimar Inst Appl Construct Res, Weimar - Germany

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T; v. 8, n. 1, p. 494-502, JAN-MAR 2019.
• Citações Web of Science: 3

Resumo

This paper compares the use of jaw and impact secondary crushing for producing coarse recycled aggregates from concrete wastes, obtained from road pavement and demolished building materials. The crushing mechanism interferes directly with recycled aggregate properties at different levels: particle size distribution, aggregate shape, generation of micro-fractures, as well as regarding the detachment of porous hardened cement paste from particle surface in order to recover pure, non-porous natural aggregates. However, crusher selection in the recycling industry is mostly carried out by acquisition and maintenance costs, industry and manufacturer traditional habits, low cost associated with second hand equipment. It also does not consider essential parameters such as the final properties of the desired end-product. Representative samples from two recycling plants were collected after primary impact crusher and secondary crushing were performed in a controlled laboratory condition through jaw and impact crushers. The aggregates attained were characterized, demonstrating similar density, porosity, particle size distribution and content of attached cement paste. Minor observed differences do not justify the common belief in the industry that impact crushers provide an improvement in the quality of recycled aggregates due to the higher detachment of cement paste from aggregates. (C) 2018 Brazilian Metallurgical, Materials and Mining Association. Published by Elsevier Editora Ltda. (AU)

• Processo FAPESP: 09/01972-0 - Reciclagem Total de Pavimentos de Concreto como Agregados para Construção de Novos Pavimentos de Concreto
• Beneficiário: Ester Tseng
• Modalidade de apoio: Bolsas no Brasil - Mestrado