Dry Lean Concrete Mix Design
(DLC Sub-Base Mix)
Dry lean concrete mix design for rigid pavement sub-base layers — achieving minimum 7-day compressive strength of 10 MPa with low cement content, zero slump and high workability under vibratory compaction.
What is the Dry Lean Concrete Mix Design?
Dry Lean Concrete (DLC) is a low cement content, zero-slump concrete used as a granular sub-base replacement for rigid pavement construction. DLC provides a stable, uniform platform for PQC construction — preventing differential settlement, moisture variation and pumping under traffic loads.
Conducted as per IRC 74 and MORTH specifications, DLC mix design targets a minimum 7-day cube compressive strength of 10 MPa using a very low cement content (150–200 kg/m³) and zero slump (10–25mm). Global Lab designs DLC mixes using actual project materials and verifies through trial mixes with standard cube testing.
Dry Lean Concrete Mix Design — Site Images
How the Dry Lean Concrete Mix Design is Conducted
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1Material TestingCoarse aggregate (max 19mm or 25mm), crusher dust/sand and cement tested per IS 383 and IS 4031.
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2Target Strength CalculationTarget mean strength = 10 MPa + 1.65σ per IRC 74 requirements.
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3Mix ProportioningVery low W/C ratio (0.35–0.45), aggregate grading and cement content optimised for zero slump.
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4Trial Mix — Compaction & StrengthDLC trial mix compacted to Proctor density. Cubes cast and tested at 7 days.
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5IRC 74 JMF Report7-day cube results vs 10 MPa minimum. Job Mix Formula issued. NABL report within 14 days.
Applicable Test Standards
| Standard | Title | Scope | Type |
|---|---|---|---|
| IRC 74 | Tentative Guidelines for Lean Cement Concrete and Lean Cement Fly Ash Concrete as a Pavement Base | DLC Design | IRC |
| MORTH | Specifications for Road and Bridge Works — Clause 601 | DLC Specification | MORTH |
| IS 516 | Methods of Tests for Strength of Concrete | Cube Testing | Indian Standard |
| IS 383:2016 | Coarse and Fine Aggregate for Concrete — Specification | Aggregates | Indian Standard |