Mejora de las propiedades viscoelásticas del asfalto ac-20 mediante la aplicación de una nanoarcilla local en mezclas de hma
- Ignacio Bladimir Cerón-Guerra
- Guillermo Loría-Salazar
- María José Cerón
- Mariela Macias
- Raúl Rodríguez
- Giovanni Sáenz-Arce
ISSN: 0378-1844
Year of publication: 2024
Volume: 49
Issue: 4
Pages: 235-247
Type: Article
More publications in: Interciencia: Revista de ciencia y tecnología de América
Abstract
The objective of this work is to improve the viscoelastic properties of local AC-20 asphalt. Ecuador has a nano clay deposit arranged in 6 levels from A1-A6, in an area of 4000 km2 . Those nano clays were treated with chemical and physical methods, using a) NaOH, b) NH3, H2O2 (molar ratio 5), and c) calcination to obtain an effective additive to be mixed with the bitumen. 532 samples were prepared, and their viscoelastic properties were measured with the dynamic shear rheometer (DSR) in the first stage. In the second stage, the best hot mix asphalt (HMA) samples were selected, and the parameters of mixing time, mixing speed, calcination temperature, and additive concentration were optimized. It was discovered that nano clay A1 calcined in the 270-275°C window activated its high level of adsorption, becoming the best additive (S1) for HMA hot asphalt mixtures. The use of 3% S1 + AC-20 and mixing times (MT) of 30, 60, 90 and 120 minutes allowed the complex modulus (G*) to increase up to 305.5%, while the phase angle δ decreased by -8.37% (MT= 90 min). The performance grade improved from PG= 64 (original) to 70, 76, and 82. These results agree with the significant adsorption capacity that this material presents.