Water-Washed Fine and Coarse Recycled Aggregates for Real Scale Concretes Production in Barcelona

Sustainability

Mikhail Konoiko¹  Miren Etxeberria¹  Carles Garcia¹  Miguel Ángel Perez² 

[1] Department of Civil and Environmental Engineering, Campus Nord, Universitat Politècnica de Catalunya·BarcelonaTECH, 08034 Barcelona, Spain;Hercal Diggers S.L., Ctra de Rubí, 286-B, 08228 Terrassa, Spain;

关键词: recycled concrete aggregate;    recycled aggregate concrete;    workability;    compressive strength;    pavement;   

DOI  :  10.3390/su14020708

来源: DOAJ

【 摘 要 】

The use of recycled aggregate to reduce the over-exploitation of raw aggregates is necessary. This study analysed and categorised the properties of water-washed, fine and coarse, recycled aggregates following European Normalization (EN) specification. Because of their adequate properties, zero impurities and chemical soluble salts, plain recycled concrete was produced using 100% recycled concrete aggregates. Two experimental phases were conducted. Firstly, a laboratory phase, and secondly, an on-site work consisting of a real-scale pavement-base layer. The workability of the produced concretes was validated using two types of admixtures. In addition, the compressive and flexural strength, physical properties, drying shrinkage and depth of penetration of water under pressure validated the concrete design. The authors concluded that the worksite-produced concrete properties were similar to those obtained in the laboratory. Consequently, the laboratory results could be validated for large-scale production. An extended slump value was achieved using 2.5–3% of a multifunctional admixture plus 1–1.2% of superplasticiser in concrete production. In addition, all the produced concretes obtained the required a strength of 20 MPa. Although the pavement-base was produced using 300 kg of cement, the concrete made with 270 kg of cement per m³ and water/cement ratio of 0.53 achieved the best properties with the lowest environmental impact.

【 授权许可】

Unknown