# Assessing Abrasion Resistance in Concrete Pavements: A Review
## 3 Mechanisms of Abrasion  
Numerous elements, including concrete's compressive strength, aggregate characteristics, the water-to-cement ratio, surface quality, kind of hardener, etc., affect every concrete pavement's ability to withstand abrasion [9; 10; 15; 16]. It is known that high-quality concrete improves macrotexture and abrasion durability under traffic stress. Adhesion and hysteresis are the two main frictional force components that contribute to pavement friction. Adhesion is contingent upon the surface's microtexture, whereas hysteresis is dependent upon its macrotexture; friction is largely influenced by both the microtexture and macrotexture [17]. It was found that slabs built using aggregates with good abrasion resistance had higher durability than slabs built with aggregates with low abrasion resistance. Therefore, longer-lasting materials with higher abrasion resistance can transfer loads more efficiently than softer materials with lower abrasion resistance [18]. Abrasion resistance is influenced by similar variables as those that determine concrete strength, such as air entrainment, the water-cement ratio, and the type and characteristics of the aggregates [11]. Concrete's resistance to abrasion is a progressive property. Surface wear is best assessed based on the close relationship between resistance and compressive strength on the wearing surface. Fine and coarse aggregates become visible when the paste degrades, and further deterioration of the hardness and aggregate-to-paste binding strength will result from impact and abrasion [15]. To reduce this effect, it is advised to utilize tougher, improved-quality aggregates in locations where tire chains and studded tires are employed [16]. Since abrasion is a progressive phenomenon, during the first stage, the process of cement stone disintegration, solvation shells, and the exposure of aggregate grains take place. The second stage is the regular operating stage, during which the cement-sand matrix and coarse aggregate grains abrasively wear down at varying rates based on their physical characteristics. In the third stage, the concrete surface undergoes destruction, wherein two scenarios could occur: (i) for concrete with a low-strength cement-sand matrix, fatigue failure of the matrix (extensive microcracking) between the coarse aggregate grains results in its loss, as shown in Figure 1; (ii) and it shows fatigue macroracks propagating on the border between the coarse aggregate grains and cement-sand matrix, which is typical of high-strength concrete [14]. Particle movement under cycling loading causes the aggregate in the pavement to abrasively wear down. Standardized test procedures are necessary to assess the abrasion resistance of concrete to ensure uniformity and comparability of findings. Abrasion in concrete is tested by grinding the sample in accordance with the standard procedure, and volumetric loss is calculated [19]. ASTM standard test procedures are widely used for assessing concrete resistance to different kinds of abrasive operations. A procedure for assessing the abrasion resistance of concrete using the sandblasting technique is presented in ASTM C 418. Using a revolving cutter machine, the ASTM C 944 test technique determines the concrete's resistance to abrasion [20]. While the ASTM C 779 method evaluates the abrasion resistance of horizontal concrete surfaces using either a rotating-disc machine or a ball-bearing machine, as shown in Figure 2, the ASTM C 1138 technique evaluates the resistance of concrete surfaces exposed to the abrasive action of water-borne particles on hydraulic structures [21]. The Bohme disc method is a technique that uses a revolving disc to assess the abrasion resistance of concrete. In this test, a sample is placed underneath an abrasive-coated steel disk that rotates while a predetermined load is applied. The material's resistance to wear is evaluated by measuring the volume or weight loss after a specified number of rotations.