Suitability of recycled concrete aggregates from precast panel buildings deconstructed at expired lifespan for structural use

Autor: Václav Venkrbec, Uroš Klanšek
Rok vydání: 2020
Předmět:
Zdroj: Journal of Cleaner Production. 247:119593
ISSN: 0959-6526
DOI: 10.1016/j.jclepro.2019.119593
Popis: This paper presents experimental research conducted to verify the suitability of a specific type of recycled aggregate concrete (RAC) for structural use. The recycled concrete aggregates (RCA) used in the RAC mixtures considered here were obtained from precast panels taken from high-rise buildings, which are typical residential structures in former Eastern Bloc countries of the European continent. Precast panels from these buildings are often considered to be unsuitable sources for structural RAC mainly on account of their poor material base and the low-skilled construction workforce and questionable quality control involved in their production. The scope of testing was determined according to guidelines stated in the EN 206-1 standard. During the execution of the tests, the following characteristics were determined for the RCA: particle size distribution; amount of fine particles; particle density; water absorption; shape index and Los Angeles abrasion resistance. Afterwards, RAC specimens were prepared on the basis of recipes developed in accordance with the EN 12390 standard, and underwent tests which evaluated the following properties: slump; air content; fresh concrete density; compressive strength; flexural strength; hardened concrete density and water absorption. The gained test results show the technical suitability of the tested RCA sources for producing medium strength structural RAC. The obtained RCA water absorption values are relatively high compared to natural aggregate (NA), and the 28-day strengths exhibited by most of the RAC specimens are one class lower than the target values. In spite of these deficiencies, the tested RCA still can be classified as suitable for medium strength structural RAC provided that these predispositions are taken into account during recipe design. The necessity to test the properties of RCA, as soon as its source is taken into consideration, reduces possibilities for general conclusions. Nevertheless, the paper provides concrete manufacturers with practically applicable information for the processing of precast panels from deconstructed buildings, gathering a suitable RCA and the production of structural RAC.
Databáze: OpenAIRE
Externí odkaz: