Wet Mix Macadam
(IS 2386 / MORTH Clause 406)

Complete physical and mechanical testing of Wet Mix Macadam (WMM) aggregate as per MORTH Clause 406 and IS 2386 — verifying grading, aggregate impact value, Los Angeles abrasion, flakiness, elongation, plasticity and water absorption for NHAI highway base course acceptance.

Overview

What is the Wet Mix Macadam (WMM) Testing?

Wet Mix Macadam (WMM) is a superior mechanically prepared base course used in modern highway construction as a replacement for WBM. In WMM, crushed aggregates are pre-mixed with a controlled quantity of water in a mixing plant before laying — ensuring uniform moisture distribution, better workability and superior compaction compared to traditional water-bound methods.

At Global Lab, WMM testing is conducted as per MORTH Clause 406 and IS 2386 covering particle size distribution (one single grading — 0 to 53mm per MORTH Table 400-8), Aggregate Impact Value (AIV ≤30%), Los Angeles Abrasion Value (LAA ≤40%), combined flakiness and elongation index (≤30%), plasticity index of fraction passing 425μm (≤6), specific gravity and water absorption — mandatory tests for NHAI, MSRDC and all state PWD highway projects.

MORTH Clause 406 Compliance

Complete grading and mechanical test suite per MORTH Table 400-8 for WMM base course.

Aggregate Impact Value (AIV ≤30%)

Stricter than WBM — maximum 30% AIV for WMM confirms higher quality aggregate requirement.

Combined Flakiness & Elongation ≤30%

Both shape indices combined per MORTH Clause 406 — single 30% limit for WMM.

Plasticity Index of Fines ≤6

Plasticity of fraction passing 425μm tested — limits clay content for quality WMM mix.

NABL Certified Reports

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

Field Density Acceptance

In-situ compaction of laid WMM layer verified by sand replacement per IS 2720 Part 28.

Test in Action

Wet Mix Macadam (WMM) Testing — Site Images

Wet Mix Macadam Base Course Laid on Highway Project

WMM Grading Sieve Analysis Against MORTH Table 400-8

Aggregate Impact Value Test per IS 2386 Part 4

Test Procedure

How the Wet Mix Macadam (WMM) Testing is Conducted

1

Sample Collection

Representative WMM aggregate sample collected from plant stockpile or road layer per IS 2386 Part 1. Field sample of minimum 50kg reduced by quartering or riffle box to test portions.
2

Particle Size Distribution

Dried sample sieved through IS sieve series (53mm down to 75μm). Grading curve plotted against MORTH Clause 406 Table 400-8 single grading envelope.
3

Aggregate Impact & Abrasion Tests

Aggregate Impact Value tested per IS 2386 Part 4 (≤30% MORTH limit). LA Abrasion tested per IS 2386 Part 4 (≤40% MORTH limit).
4

Shape, Plasticity & Absorption Tests

Combined flakiness + elongation index per IS 2386 Part 1 (≤30%). Plasticity index of minus 425μm fraction per IS 2720 Part 5 (PI ≤6). Specific gravity and water absorption per IS 2386 Part 3.
5

MORTH Compliance Report

All results compared against MORTH Clause 406 acceptance limits. NABL report with pass/fail compliance statement issued within 7 days.

Standards & Specifications

Applicable Test Standards

Standard	Title	Scope	Type
MORTH Clause 406	Specifications for Road and Bridge Works — Wet Mix Macadam	WMM Specification	MORTH
IS 2386	Methods of Test for Aggregates for Concrete (Parts 1, 3, 4, 5)	Aggregate Testing	Indian Standard
IRC 37	Guidelines for the Design of Flexible Pavements (5th Revision)	Pavement Design	IRC
IS 2720 Part 5	Methods of Test for Soils — Determination of Liquid and Plastic Limit	Plasticity Index	Indian Standard

Applications

Where is the Wet Mix Macadam (WMM) Testing Used?

NHAI national highway WMM base course aggregate acceptance testing

State expressway and major highway WMM material quality verification

Urban arterial road and city bypass WMM base layer acceptance

Airport runway sub-base and base course WMM aggregate testing

Industrial road and port access road WMM base course quality control

Quarry source approval for WMM aggregate suppliers on large highway projects

Why Choose Global Lab

Our Advantages

NABL Accredited ReportsLegally valid MORTH Clause 406 certificates accepted by NHAI, MSRDC and all PWD authorities.

Stricter Than WBM — AIV ≤30%WMM's stricter AIV limit reflects its use on higher-standard highways — our lab tests to exact MORTH limits.

Plasticity Index TestingPI of minus 425μm fraction tested alongside grading — unique to WMM specification.

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

Fast 7-Day ReportComplete MORTH Clause 406 test suite reported within 7 days.

Complete Road PackageWMM + CRM + WBM + GSB + Field density as a complete road QC package.

Wet Mix Macadam(IS 2386 / MORTH Clause 406)