Crusher Run Macadam Base Testing
(CRM — IS 2386 / MORTH Clause 401)

Complete physical and mechanical testing of Crusher Run Macadam (CRM) base course material as per MORTH Clause 401 and IS 2386 — verifying grading, aggregate impact value, abrasion, flakiness, water absorption and CBR for road base layer acceptance.

Overview

What is the Crusher Run Macadam Base Testing?

Crusher Run Macadam (CRM) is a mechanically crushed and graded aggregate base course material used in flexible pavement construction. It consists of crushed stone aggregate of varying sizes — from 75mm down to dust — which when compacted forms a dense, interlocked matrix providing high load-bearing strength, stability and drainage for the pavement structure above.

At Global Lab, CRM testing is conducted as per MORTH Clause 401 and IS 2386 covering particle size distribution (grading check against MORTH Table 400-1), Aggregate Impact Value (AIV ≤30%), Los Angeles Abrasion Value (LAA ≤40%), flakiness index (≤30%), water absorption, specific gravity and in-situ compaction by field density test — mandatory tests for NHAI, state PWD and municipal road project acceptance.

MORTH Clause 401 Compliance

Full grading and mechanical test suite per MORTH Table 400-1 specification for CRM base course.

Aggregate Impact Value (AIV ≤30%)

Resistance to impact loading — maximum 30% per MORTH for CRM base course application.

LA Abrasion Value (≤40%)

Resistance to degradation under traffic — Los Angeles abrasion test per IS 2386 Part 4.

Particle Size Distribution

Grading plotted against MORTH Table 400-1 envelope — ensures correct blend of sizes.

NABL Certified Reports

All test and calibration results are backed by traceable measurements and standardized procedures.

Field Density Acceptance

In-situ compaction verified by sand replacement method per IS 2720 Part 28.

Test in Action

Crusher Run Macadam Base Testing — Site Images

Crusher Run Macadam Base Course Layer on Road Project

Sieve Analysis — Grading Check Against MORTH Table 400-1

Aggregate Impact Value Test per IS 2386 Part 4

Test Procedure

How the Crusher Run Macadam Base Testing is Conducted

1

Sample Collection

Representative sample collected from stockpile or in-situ layer per IS 2386 Part 1 procedure. Minimum 50kg field sample reduced to test portions.
2

Particle Size Distribution

Dried sample passed through IS sieve series (75mm to 75μm). Grading plotted against MORTH Clause 401 Table 400-1 upper and lower limits.
3

Aggregate Impact & Abrasion Tests

AIV tested per IS 2386 Part 4 using impact testing machine. LA Abrasion tested per IS 2386 Part 4.
4

Flakiness, Specific Gravity & Absorption

Flakiness index per IS 2386 Part 1. Specific gravity and water absorption per IS 2386 Part 3.
5

MORTH Compliance Report

All results compared against MORTH Clause 401 acceptance criteria. NABL report with pass/fail statement issued within 7 days.

Standards & Specifications

Applicable Test Standards

Standard	Title	Scope	Type
MORTH Clause 401	Specifications for Road and Bridge Works — Granular Sub-Base and Base Course	CRM Base	MORTH
IS 2386	Methods of Test for Aggregates for Concrete (Parts 1, 3, 4)	Aggregate Testing	Indian Standard
IRC 37	Guidelines for the Design of Flexible Pavements	Pavement Design	IRC
IS 2720 Part 28	Methods of Test for Soils — Determination of Dry Density by Sand Replacement	Field Density	Indian Standard

Applications

Where is the Crusher Run Macadam Base Testing Used?

NHAI national highway flexible pavement CRM base course acceptance testing

State highway and MDR road construction CRM quality control

Urban road and municipal pavement CRM base layer material verification

Airport apron and taxiway sub-base and base course aggregate testing

Industrial road and heavy-vehicle parking area CRM material acceptance

Quarry source approval testing for CRM aggregate suppliers on large projects

Why Choose Global Lab

Our Advantages

NABL Accredited ReportsLegally valid MORTH Clause 401 compliance certificates accepted by NHAI and all PWD authorities.

Complete MORTH Test SuiteGrading + AIV + LAA + Flakiness + Specific gravity in one submission and report.

NHAI Project ExperienceExtensive CRM and road aggregate testing experience for NHAI, MSRDC and state highway projects.

Pan-India CoverageAggregate testing teams at all 7 NABL-accredited lab locations across India.

Fast 7-Day ReportComplete MORTH Clause 401 test suite reported within 7 days of sample receipt.

Combined Road Testing PackageCRM + WMM + GSB + Field density offered as a complete road QC package.

Crusher Run Macadam Base Testing(CRM — IS 2386 / MORTH Clause 401)