Durability evaluation of reclaimed asphalt pavement, ground glass and carbide lime blends based on unconfined compression tests
Introduction
Road transportation is the most important in Brazil, since the largest portion of cargo and passenger movement occurs through road vehicles. Updated data show that 61% of cargo transport and 95% of passenger transport are carried out on the country's road system [19]. Likewise, in the USA, approximately 66% and 88% of the cargo and passengers, respectively, is transported through the road network [17].
Comprising a large and significant portion of the transportation structure, the highways constantly show concerning problems, such as potholes, rutting and fatigue cracking in the pavement, which require continuous maintenance. Sometimes, it is necessary to use milling for surface recovery of the pavement, and the removed material is a waste known as ‘reclaimed asphalt pavement’ (RAP), which can easily reach large volumes that are usually landfilled. However, the use of recycled materials in the construction industry and, in particular, in transportation works, has been widely studied in recent years, as it is an economically viable technical alternative to traditional techniques [32]. RAP, specifically, takes advantage of the aged pavement aggregate to be reused in new pavement layers, as long as it meets the specifications and shows an adequate support capacity, adjusted to the requirements of the new road.
The mechanical performance of the RAP was already studied by several authors, with or without stabilizing agents such as Portland Cement [62], [52], [61], [4], [38], [35], [36], [46], [34], [39], [49], [23]) . Likewise, several studies addressed its influence on the durability performance of mortars and concretes [1], [2], [57]) or when reapplied in pavements [44], [15], [37], [12], [58], [45], [40], [54]. The RAP alone might not show sufficient support capacity to be the main material in base and sub-base layers, thus the need for stabilization. However, the need for alternative construction materials is not limited to natural aggregates, but it extends also to Portland Cement, responsible for 5% to 7% of the CO2 global emissions [59]. In this sense, new cementitious materials, with a more sustainable footprint, are necessary to sustain a less aggressive development. Cementitious materials based on pozzolanic residues and calcium hydroxide can reduce CO2 emissions, responsible for the greenhouse effect, and can be a partial alternative to Portland cement in the construction industry.
A pozzolanic material, in general, needs to have three basic characteristics: a high silica content, with a high degree of amorphization, and a large specific surface area. In comparison with fly ash and silica fume, common glass has enough silica content to satisfy, when finely ground, the basic requirements of a pozzolanic behavior [55]. Non-recycled residual glass stands out as an environmental problem in urban centers since it occupies significant portions of the available landfills. Glass recycling rates vary worldwide, with around 90% in the European Union, 95% in Switzerland, 40% in the United States and 45% in Brazil [63], [14]. Soda-lime glass is the main constituent of glass containers and flat glass and corresponds to about 85% of the total amount of glass produced annually worldwide [43].
In this context, this article seeks to obtain a viable solution, from the engineering point of view, to contribute to the recycling of waste glass and, subsequently, to the economy and sustainability, through the study of the mechanical and physical behavior of a combination of three residues, i.e. reclaimed asphalt pavement, ground glass waste and carbide lime. Unconfined compression and split tensile strength tests, together with durability (wetting and drying) and stiffness (ultrasonic pulse velocity) tests, were performed and interpreted, to assess the overall performance of the newly proposed material. In addition, a correlation between the durability and compression strength results was proposed.
Section snippets
Materials
The RAP was obtained from the pavement segments of the BR-290 highway, in southern Brazil. It was dried in the laboratory at a controlled temperature of 60 °C, for two days. The finer fraction of the final granular mixture was formed by transparent flat glass waste commonly used in windows, after grinded in a ball mill for 3 h. X-ray diffraction (XRD) showed that the ground glass has some degree of amorphization, translated by the halo approximately located between the 18° and 35° (2θ), but it
Unconfined compression and split tensile strength
In the case of the unconfined compression and split tensile strength, a relationship for both is expressed as a function of the adjusted porosity-volumetric binder content index (η/Biv) proposed by Consoli et al. [24]. Porosity (η) was defined by the relationship between the ratio of voids (in volume) and the total volume of the specimen (V), as similarly outlined by Consoli et al. [21], through Eq. (2). The volumetric binder content (Biv) is expressed by the relation between the volume sum of
Conclusions
The present paper aimed to evaluate the performance of a mixture composed of three different residues (RAP, GG and CL) for strength, stiffness and durability tests. Moreover, it is also proposed an approach for the evaluation of the durability test through the unconfined compression test, which was extensive to several soils found in literature. From the data presented in this manuscript, the following conclusions can be drawn:
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The usage of the adjusted porosity/binder index to portray the
Author statement
The present review addresses all the comments from the reviewers, without any situation where such response showed some difficulty or a difference of opinions. We thus believe that this new version of the paper is an improvement, regarding the first version.
Declaration of Competing Interest
The authors declare that they have no conflict of interest.
References (63)
- et al.
Influence of RAP aggregates on strength, durability and porosity of cement mortar
Constr Build Mater
(2018) - et al.
Effects of Reclaimed Asphalt Pavement aggregates and mineral admixtures on pore structure, mechanical and durability properties of cement mortar
Constr Build Mater
(2019) - et al.
Durability and long term performance of geopolymer stabilized reclaimed asphalt pavement base courses
Construct Build Mater
(2016) - et al.
Experimental study on the use of rejuvenators and plastomeric polymers for improving durability of high RAP content asphalt mixtures
Constr Build Mater
(2017) - et al.
A unique relationship determining strength of silty/clayey soils: Portland cement mixes
Soils Found
(2016) - et al.
The effects of curing time and temperature on stiffness, strength and durability of sand environment friendly binder blends
Soils Found
(2019) - et al.
Environmental risks of using recycled crushed glass in road applications
J Cleaner Prod
(2012) - et al.
Effect of ageing and RAP content on the unduction healing properties of asphalt mixtures
Constr Build Mater
(2018) - et al.
Practical recycling applications of crushed waste glass in construction materials: a review
Constr Build Mater
(2017) - et al.
Effect of long-term ageing on properties of RAP inclusive WMA mixes
Constr Build Mater
(2019)
Studies on concrete containing ground waste glass
Cement Concr Res
Effect of mineral admixtures on fresh, mechanical and durability properties of RAP inclusive concrete
Constr Build Mater
Reclaimed asphalt pavement and recycled concrete aggregate blends in pavement subbases: laboratory and field evaluation
J. Mater. Civ. Eng.
Sustainable use of recycled-glass powder in soil stabilization
J Mater Civ Eng
Commitment business for recycling: review
A new method for determining the tensile strength of concrete
Key parameters for strength control of artificially cemented soils
J Geotech Geoenviron Eng
Variables governing strength of compacted soil-fly ash-lime mixtures
J Mater Civ Eng
Key parameters controlling dynamic modulus of crushed reclaimed asphalt paving–powdered rock–Portland cement blends
Road Mater Pavement Des
Durability, strength, and stiffness of green stabilized sand
J Geotech Geoenviron Eng
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