Waste Not, Want Not: Sustainable Use of Anti-Stripping-Treated Waste Ceramic in Superpave Asphalt Mixtures

Abstract

This research studied the sustainable utilization of waste ceramic in asphalt mixtures by substituting fine aggregate with treated and untreated waste ceramic produced from construction and demolition activities. To improve its adhesion to the asphalt binder and lower the moisture susceptibility of Superpave asphalt mixes, the waste ceramic was treated with a silane anti-stripping agent. The Marshall quotient (MQ), Marshall stability (MS), indirect tensile strength (ITS), retained Marshall stability (RMS), and tensile strength ratio (TSR) were used to assess the mechanical performance and moisture susceptibility of all mixes. The changes in the chemical composition, synergy, physical state, and microstructure of the studied composites were also investigated using Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The results revealed that substituting fine aggregate with 50% silane-treated waste ceramics reduced permanent deformation by 46%. Moreover, integrating silane-treated ceramics reduced asphalt mixture moisture susceptibility, with an RMS value of 87.7% obtained for asphalt containing 75% treated ceramic particles. The application of a silane anti-stripping agent resulted in high adhesion between the ceramic particles and bitumen as well as the production of fewer air voids in the mixes due to the formation of strong CH aromatic linkages, as well as Si-O and Si-O-Si bonds. The possibility of employing waste ceramics in asphalt mixes as a sustainable alternative to virgin aggregates while decreasing environmental impacts and improving resource efficiency is highlighted in this paper.

Sustainability Enhancement through High-Dose Recycled Tire Steel Fibers in Concrete: Experimental Insights and Practical Applications

“…The percentage comparison of the experimental and empirically computed WAs is demonstrated in Figure 17. It can be observed that the WA values predicted by Equation (2) align more closely with the observed values compared to Equation (1). The errors associated with Equation (1) ranged from 0.4% to 3.4%, while Equation (2) exhibited errors ranging from 0.2% to −1.6%.…”

“…Equation (1) relates WA to the cylindrical compressive strength (CS, in MPa) of the concrete, while Equation (2) relates WA (%) to the indirect tensile strength (SS, in MPa). Theoretical Equations ( 1) and ( 2) are developed using experimental data from the current study and showed good correlation with the data (R 2 = 0.58 for Equation (1) and R 2 = 0.88 for Equation (2)).…”

“…However, certain waste materials pose significant challenges when transforming them into useful resources. Solid waste materials that cannot be efficiently recycled are often repurposed and incorporated into different materials and products, such as utilizing anti-stripping-treated waste ceramic in superpave asphalt mixtures [1], silane-treated waste glass powder in concrete pavement [2], bagasse ash in asphalt concrete pavements [3], water treatment sludge and stone dust in concrete [4], and recycled waste glass in ultra-high-performance concrete [5]. One example of a major solid pollutant is discarded tires, which can take up to 100 years to degrade when exposed to the open air [6][7][8].…”

Empirical Model for the Retained Stability Index of Asphalt Mixtures Using Hybrid Machine Learning Approach

“…where S 1 is the stability of the conditioned samples after being submerged in water for 24 h and S 2 is the stability of the control samples after being submerged for 30 min. It should be mentioned that 75% of RSI is the minimum satisfactory limit for a durable mix of asphalt [14,43,44]. The RSI results indicated that some testing groups of samples were prone to moisture damage by means of average RSI values of less than 75%.…”

“…Some of the tests include immersed wheel-tracking configurations such as the Hamburg wheel-tracking test and the Asphalt Pavement Analyzer device [9,10], while others evaluate moisture damage by calculating the ratio of strength or stiffness of water-conditioned compacted Hot-Mix Asphalt (HMA) samples to that of unconditioned samples [4]. The latter includes several testing protocols such as the immersion-compression test, the resilient modulus test, the double-punch method, the tensile strength ratio (TSR) or modified Lottman (AASHTO T 283), the Retained Stability Index (RSI), and others [11][12][13][14]. Even though these testing procedures help compare the moisture susceptibility of different mixtures, they do not provide information about the proper characteristics of asphalt mixes.…”