# Assessing Abrasion Resistance in Concrete Pavements: A Review
## 4 Factors Affecting Abrasion Resistance
### Influence of Material Properties  
#### 4.1.1 Aggregate  
Since aggregates make up about 75% of the volume of concrete, the strength, mobility, and durability of concrete are all influenced by the physical, thermal, and chemical characteristics of the aggregates [32]. The aggregates must be durable and resistant to abrasion to avoid crushing, deterioration, and disintegration whether they are stacked, go through an  
Figure 4: Abrasion resistance at different test sections for center lane and wheel path. asphalt plant, or are placed in a payer that has been compressed using rollers and exposed to traffic loadings [33]. While the aggregate is typically thought of as an inert filler in concrete, this is not always the case. Aggregates may react with the alkalis in cement, leading to deterioration and expansion. To enhance strength, special aggregates can be used in a high-strength topping combination or by using the dry-shake approach. If the primary concern is abrasion, adding premium quartz, traprock, or all aggregates proportionately balanced with cement enhances the wear resistance by increasing the compressive strength at the surface. To further increase the abrasion resistance and prolong the surface life, utilizing a cement and metallic aggregate combination can be considered [15]. A study carried out to understand the abrasion resistance of samples of different types of igneous, metamorphic, and sedimentary rock showed that igneous rock shows more resistance to abrasion compared to sedimentary and metamorphic type rock, as shown in Figure 5 [33]. Throughout the lifespan of aggregate materials, the shape of the aggregate changes by corner breaking, surface erosion, and crushing due to varying loads and impacts [34]. The study showed that the aggregate's angularity value significantly decreased during abrasion, and these decreases agreed with the abrasion test results, suggesting that angularity reduction was the primary cause of abrasion loss. In contrast, no discernible difference in the coarse aggregates' surface texture before and after abrasion was found [35]. The experiment carried out in different types of aggregates showed that for the same strength combinations, the Los Angeles abrasion values of the aggregates were inversely correlated with the fracture energy property of PCC [36]. Hardened cement paste often has a low resistance to abrasion. It is preferable to utilize a firm coarse aggregate and paste with low porosity and high strength to create concrete with a high abrasion resistance [37]. In the case of CRCP, abrasion-resistant, larger aggregates encourage strong aggregate interlock, which improves load-transfer efficiency [38]. The impact of aggregate strength and texture on concrete's compressive strength and abrasion resistance was examined by [PERSON] et al. [39]. They found that concrete with the gabbro aggregate had the highest compressive strength and abrasion resistance, whereas concrete with sandstone had the lowest. As shown in Figure 6, the abrasion loss was found to decrease as the compressive strength of the rock increased. They proposed  
Figure 5: Effect of physical and mechanical properties on LAA loss of sedimentary, metamorphic, and igneous rocks [33]. that an aggregate with high abrasion resistance be used to generate concrete with high abrasion resistance. [PERSON] et al. [40] evaluated the abrasion resistance of concrete using four different types of granite, limestone, dolomitic limestone, and trap rock of coarse aggregates. They assessed the concrete mixes in accordance with ASTM C779 and used the Los Angeles (LA) abrasion test to estimate the abrasion loss of each aggregate. According to their research, abrasion loss was greatest in limestone and lowest in granite and trap rock. Furthermore, the findings showed a correlation between the concrete mixes' abrasion resistance and aggregate strength, with softer rocks enduring noticeably more wear than tougher granite and trap rock.