Mechanical behaviour of self-compacting concrete made with recovery filler from hot-mix asphalt plants

• Published in: Construction & building materials 2017-01, Vol.131, p.114-128
• Main Authors: Esquinas, A. Romero, Ramos, C., Jiménez, J.R., Fernández, J.M., de Brito, J.
• Format: Article
• Language: English
• Subjects: Carbonation processes; Chemical properties; Comparative analysis; Concretes; Fillers (Materials); Mechanical properties; Pozzolanic reactions; Recovery filler; Self-compacting concrete; Shrinkage; Siliceous filler; Thermogravimetry; Ultrasonic pulse velocity
• ISSN: 0950-0618; 1879-0526
• DOI: 10.1016/j.conbuildmat.2016.11.063

[Display omitted] •A comparative study of two types of SCC was carried out.•The aging mechanism of the SCC mixes (SCC-SF and SCC-RF) was different.•Pozzolanic reactions occurred during curing of the SCC-SF.•Shrinkage in the SCC-RF was lower because of the larger particle size.•Recovery filler from hot mix asphalt plants is adequate to produce SCC. The aim of this paper is to assess the feasibility of the use of a fine grain waste generated in hot-mix asphalt plants (HMA), namely recovery filler (RF), as filler materials in self-compacting concrete (SCC) production. A comparative study of two types of SCC was performed. The first concrete type was made incorporating recovery filler (SCC-RF) of a dolomitic nature and the second was made with commercial siliceous filler (SCC-SF), the latter used as reference. Good results of self-compatibility were obtained using RF. The thermogravimetric study showed that in SCC-SF the higher loss weight occurs in the dehydration zone (0–400°C) and in SCC-RF it occurs in the decarbonation area (550–735°C). The aging mechanism of both concrete types (SCC-SF and SCC-RF) was different. In the SCC-SF mixes, portlandite undergoes carbonation processes and pozzolanic reactions and in the SCC-RF mixes it only undergoes carbonation processes. The experimental results (splitting tensile strength, flexural strength and static modulus of elasticity) show the validity of using EHE-08, initially proposed for NVC (Normally Vibrated Concrete), in SCC. The ultrasonic pulse velocity values for SCC-SF was greater than for SCC-RF, which can be attributed to compacity and compressive strength. The shrinkage behaviour was better in SCC-RF than SCC-SF, mainly due to the greater particle size of recovery filler (RF), although the SCC-RF mixes showed lower density and mechanical strength than SCC-SF. In short, the SCC manufactured with recovery filler from plants manufacturing hot-mix asphalt (HMA) – SCC-RF – is expected to have better features than SCC-SF in relation to shrinkage and early appearance of cracks.