In highway projects, aggregates form the backbone of both flexible and rigid pavements. Their strength, shape, toughness, and wear resistance directly influence performance under traffic loads and environmental conditions.
Aggregates used in highway layers must:
Aggregate testing is a key part of material acceptance under MoRTH Specifications and relevant IS standards — ensuring safety, performance, and compliance before use in construction stages.
Purpose: Measures the toughness of aggregates — the ability to resist sudden impact or shock.
Why it matters: Impact resistance is critical for aggregates used in base courses and surface layers subjected to dynamic loads and vibrations. Lower AIV means better toughness and performance.
Purpose: Evaluates the abrasion and wear resistance of aggregates by simulating abrasive and impact forces.
Why it matters: This is one of the most widely used aggregate durability tests. It helps ensure that coarse aggregates can endure repeated traffic loading and abrasion without excessive degradation.
👉 Read the full LA Abrasion guide
Purpose: Determines the resistance of aggregates to crushing under gradually applied compressive loads.
Why it matters: Crushing resistance is essential for load-bearing capacity in base, sub-base, and concrete pavement layers.
Purpose: Assesses the shape characteristics of aggregates — how flaky or elongated the particles are.
Why it matters: Flaky and elongated particles reduce stability and compaction in both bituminous and concrete mixes.
👉 Read the full Flakiness & Elongation guide
Purpose: Measures the porosity of aggregates by determining water absorption percentage.
Why it matters: Porosity impacts concrete mix design, workability, and long-term durability.
👉 Read the full Water Absorption guide
Aggregate quality control isn’t just about one test — it’s about understanding strength, toughness, wear resistance, shape, and porosity:
Consistent testing maintains pavement quality from sub-base through surface courses.
AIV measures impact toughness while Los Angeles measures abrasion resistance — both together give a more complete durability profile.
Yes — some aggregates with low abrasion loss in lab may behave differently in real conditions; combining tests improves prediction reliability.
Los Angeles Abrasion Test is commonly used for wearing courses due to its simulation of impact and abrasion forces.
Test results inform material selection, compaction strategies, and proportioning in both concrete and bituminous mixes.
Aggregate testing ensures safe, durable, and specification-compliant highway pavements. This pillar page acts as a central reference hub — each test links to a detailed procedure guide for engineers and QA/QC teams.
Key tests for coarse and fine aggregates in highway pavements as per IS & MoRTH standards:
