Influence of four non-conventional additives on the physical, rheological and thermal properties of an asphalt

Miguel Gerardo Delgado Jojoa,Fredy Alberto Reyes Lizcano,Wilmar Darío Fernández Gómez,Jessica Alexandra Sánchez Gilede,Hugo Alexander Rondón Quintana

doi:10.15446/ing.investig.v38n2.68638

Abstract

This article shows the evaluation of the influence of two polymer wastes (crumb rubber – GCR and low density polyethylene – LDPE), a natural bitumen (Gilsonite - G) and a chemical component (Husil) about the physical, rheological and thermal properties of an asphalt cement (AC 60/70 penetration grade). Over a control asphalt and the modified asphalts were performed: penetration, softening point, ductility, ignition point, rheology (using a dynamic cut rheometer – DSR), Multi Stress Creep and Recovery (MSCR), linear amplitude sweep (LAS), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) tests. The results show that fourth additives increase the stiffness and rutting resistance of the asphalts. Additionally, it reports an increase in fatigue cracking resistance when asphalt cement is modified with GCR, G and Husil. The additives give thermal stability to the asphalt cement, providing less mass loss (linked mostly to a less oxidation).

Highlights

Motivation and objective rate of products from the agriculture sector, manufacture, mining and cattle growth is 5.47%, 14.82%, 19.11% and 4.88%, respectively (MINTRANSPORTE, 2008)
When entering in contact with the asphalt cement in an approximate temperature of 70oC the Husil material makes the asphalt turns into foam, decreasing its viscosity and making easier the work processes and mix compatibility (Rondón et al, 2016a)
For the four non-conventional additives the following characteristics were considered (Figure 1): a) the granular crumb rubber (GCR) from scrap rubber tires, was mechanically grinding to obtain particles less than 6.3mm; b) the low density polyethylene (LDPE) was obtained of waste coffee straws, that were cut in order to pass the sieve No 4 and were retained in the No 10; c) the Gilsonite was obtained from a mine localized in the Cesar State (Colombia); d) the Husil was obtained in liquid base

Summary

Introduction

Motivation and objective rate of products from the agriculture sector, manufacture, mining and cattle growth is 5.47%, 14.82%, 19.11% and 4.88%, respectively (MINTRANSPORTE, 2008). The Gilsonite (G) is a type of natural asphalt known in the world because its higher point of softness, low viscosity and stiffness due to its asphaltenes contents (Widyatmoko et al, 2005; Cholewińska & Iwański, 2011; Esfeh et al, 2011; Ameri et al, 2011, 2012; Rondón et al, 2016) The former generates a notable increase in the asphalt stiffness when it is used as an additive, leading more resistant mixes in high temperatures sites (Feng et al, 2011, 2011a; Jahanian et al, 2017; Yilmaz & Yamaç, 2017). According to Rondón et al (2016a, 2017), the Husil allows to reduce the temperature of the mix in approximately 30oC, achieving the increase of the resistance under the monotonic and dynamic loads

Methods

Results

Conclusion