IS 383:2016 is the Indian Standard (BIS) for coarse and fine aggregates for concrete - specification. This standard specifies the physical properties, mechanical limits, and grading requirements for naturally sourced, manufactured, and alternative (recycled) coarse and fine aggregates for use in concrete. It is the fundamental standard for evaluating aggregate quality for concrete mix design in India.
Specifies requirements for coarse and fine aggregates derived from natural sources for concrete.
Gradation, deleterious limits, chloride/sulphate caps, soundness, flakiness/elongation and abrasion limits for fine and coarse aggregates including M-sand.
| Reference | Value | Clause |
|---|---|---|
| Coarse aggregate — max nominal sizes | 10, 12.5, 16, 20, 40 mm | Cl. 6.2 (Table 7) |
| Fine aggregate — gradation zones | Zone I (coarsest) → Zone IV (finest) | Cl. 6.3 (Table 9) |
| Fine aggregate — Zone II passing 600 µm | 35–59 % | Cl. 6.3 (Table 9) |
| Manufactured sand (M-sand) — passing 150 µm (max) | 20 % (vs 10 % for natural) | Cl. 6.3 (Table 9) |
| Water absorption — coarse aggregate (max) | 2 % by mass | Cl. 5.4.1 |
| Water absorption — fine aggregate (max, M-sand) | Reported (typically <2 %) | Cl. 5.4.1 |
| Specific gravity — natural aggregate (typical)— report value, not a limit | 2.6 – 2.8 | Cl. 5.4.1 |
| Deleterious materials — clay lumps (max) | 1.0 % (fine), 1.0 % (coarse) | Cl. 5.3.1 (Table 1) |
| Material finer than 75 µm — uncrushed coarse (max) | 3 % (concrete subject to abrasion) | Cl. 5.3.1 (Table 1) |
| Material finer than 75 µm — M-sand (max)— natural sand 3 % only | 15 % (in concrete) | Cl. 5.3.1 (Table 1) |
| Chloride content — RCC fine aggregate (max as Cl⁻) | 0.04 % by mass (≈ 600 ppm) | Cl. 5.5.1 (Table 4) |
| Chloride content — coarse aggregate RCC (max) | 0.02 % by mass (≈ 200 ppm) | Cl. 5.5.1 (Table 4) |
| Sulphate content (as SO₃) — total aggregates (max) | 0.5 % by mass | Cl. 5.5.2 |
| Flakiness index — combined (max) | 35 % (typical for road-grade) | Cl. 5.4.4 |
| Elongation index — combined (max) | 35 % (typical) | Cl. 5.4.4 |
| Soundness — Na₂SO₄ loss (max, fine) | 10 % | Cl. 5.4.6 (Table 5) |
| Soundness — Na₂SO₄ loss (max, coarse) | 12 % | Cl. 5.4.6 (Table 5) |
| Aggregate impact value (max) — wearing surfaces | 30 % | Cl. 5.4.3 |
| Aggregate crushing value (max) — wearing surfaces | 30 % | Cl. 5.4.3 |
| Los Angeles abrasion value (max) | 30 % (wearing surface), 50 % (other) | Cl. 5.4.5 |
| Alkali-aggregate reactivity — mortar bar expansion (max) | 0.10 % (innocuous) | Cl. 5.6 |
IS 383:2016 specifies requirements for coarse and fine aggregates from natural sources for concrete. It is the foundation specification referenced by IS 456:2000 and IS 10262:2019 for aggregate-related parameters.
You reference IS 383 for: - Aggregate quality acceptance at site (fineness modulus, grading, deleterious materials) - Mix design inputs — specific gravity, water absorption, bulk density - Source approval testing when switching aggregate suppliers - BOQ specification ('20 mm and 40 mm coarse aggregate conforming to IS 383:2016') - M-sand approval (added explicitly in the 2016 revision)
The 2016 revision was a major update over 1970: - Included manufactured sand (M-sand) as a recognized source - Tightened limits on deleterious materials (clay, silt, shell, mica) - Updated grading zones for fine aggregate - Added requirements for recycled concrete aggregate (RCA) in Annex C
Pair with: - IS 456:2000 — parent code requiring IS 383-compliant aggregates - IS 10262:2019 — mix design uses IS 383 grading - IS 2386 Parts 1-8 — methods of test for aggregates (grading, specific gravity, soundness, etc.) - IS 2116 — sand for plaster (separate specification, not IS 383)
IS 383:2016 Clause 4.3 classifies natural sand and M-sand into 4 grading zones based on cumulative percentage passing:
Zone I — Coarsest. High FM (3.5-4.0). Best for leaner mixes (M15-M20), floor screeds, BBS chair placement concrete. Too coarse for rich mixes (causes bleeding).
Zone II — Medium-coarse. FM (2.9-3.5). The ideal zone for most concrete (M20 through M40). Good workability, minimal bleeding, consistent strength.
Zone III — Medium-fine. FM (2.3-2.9). Use for M40+ high-strength concrete where lower water demand improves pumpability. Also acceptable for M25-M35 if Zone II unavailable locally.
Zone IV — Finest. FM (1.8-2.3). Borderline acceptable; IS 383 restricts to M15 and below. Fine sand increases water demand and cement requirement; concrete becomes uneconomical.
M-sand equivalence: Per IS 383:2016 Clause 4.3.1, M-sand from hard rock (granite, basalt, limestone) can substitute natural sand if it falls in Zones I-III grading envelope and passes deleterious limits. M-sand typically grades to Zone II or IIIa (between II and III) — generally adequate for standard concrete.
Practical tip: Always test the fine aggregate zone before mix design. A mix designed for Zone II but executed with Zone III sand will be over-sanded and lose 3-5 MPa strength. Zone testing takes 30 minutes at any accredited concrete lab.
Problem: New residential project in Pune. Delivered aggregate sample — coarse (20 mm), fine (river sand). Verify IS 383:2016 compliance.
Step 1 — Visual inspection: Coarse: Free of coatings, no visible shells/leaves, appears uniform hard rock. ✓ Fine: Slightly dark (might indicate silt), gritty feel. Test further.
Step 2 — Sieve analysis per IS 2386 Part 1: Coarse 20 mm sample (1 kg through 20, 16, 12.5, 10, 4.75 mm): - % passing 20 mm = 100 - % passing 16 mm = 92 - % passing 12.5 mm = 75 - % passing 10 mm = 35 - % passing 4.75 mm = 2 Compare to IS 383 Table 7 (graded aggregate 20 mm): Limits: 100 (passing 20 mm), 85-100 (16 mm), 67-85 (12.5 mm), 25-40 (10 mm), 0-5 (4.75 mm) → 92, 75, 35, 2 all within limits ✓
Fine sand sample (500 g through 4.75, 2.36, 1.18, 0.60, 0.30, 0.15 mm): - % passing 4.75 mm = 98 - % passing 2.36 mm = 80 - % passing 1.18 mm = 55 - % passing 0.60 mm = 32 - % passing 0.30 mm = 15 - % passing 0.15 mm = 4 Fineness modulus = (100-98 + 100-80 + 100-55 + 100-32 + 100-15 + 100-4) / 100 = 316/100 = 2.85
Compare to IS 383 Table 4 zones: - Zone II: passing 600 μm = 35-59%; 32 is just below → Zone III border - Zone III: passing 600 μm = 15-34%; 32 fits → Zone III FM 2.85 corresponds to Zone III. Acceptable for standard M25-M35 concrete. Mix design must be re-checked — if designed for Zone II, cement content may need to increase 5-10 kg/m³.
Step 3 — Deleterious material per IS 2386 Part 2: Silt content: 3.5% — IS 383 limit is 3.0% for uncrushed natural sand. Marginally non-compliant. Either reject the lot or wash at site before use. If washing reduces silt below 3.0%, mix design can proceed.
Step 4 — Specific gravity per IS 2386 Part 3: Coarse: 2.68 — normal range (2.5-2.9) for granite rock. Fine: 2.62 — normal for river sand.
Step 5 — Water absorption: Coarse: 0.6% — below 2.5% limit. ✓ Fine: 1.2% — below 2.0% limit. ✓
Step 6 — Alkali-aggregate reactivity (AAR) per IS 2386 Part 7: Mandatory check if cement alkali content > 0.6% Na₂O equivalent. Skipping this test has caused severe durability issues in South India (Karnataka, Kerala coastal zones).
Decision: - Coarse aggregate: ACCEPT. Specifications met. - Fine aggregate: CONDITIONAL ACCEPT. Wash to reduce silt below 3.0%, then approve for M25-M35. Adjust mix design for Zone III grading.
Re-test at every new supplier change or every 200 tonnes of delivery.
1. Skipping zone classification at site. Most sites accept fine aggregate on visual inspection alone. Without sieve analysis, you don't know if the sand is Zone II, III, or worse. Mix design based on wrong zone over-proportions cement or under-strengths concrete. 30-minute test per batch prevents this.
2. Ignoring the 2016 M-sand provisions. Old drawings and DBRs still specify 'natural river sand per IS 383:1970'. With natural sand mining restrictions across many Indian states, M-sand is the only practical supply. IS 383:2016 Clause 4.3.1 explicitly allows M-sand — update your specs to reference IS 383:2016 and accept M-sand meeting Zone II/III grading.
3. Using 40 mm aggregate for heavily reinforced work. IS 383 permits 40 mm MSA, but for heavily reinforced sections (columns, beams with dense rebar), 20 mm or 12.5 mm gives better compaction around bars. Clause 5.3 of IS 456 requires MSA ≤ 0.75 × minimum clear spacing between bars. Violating this traps aggregate between bars and creates honeycomb.
4. Not testing alkali-aggregate reactivity in South India. Coastal and South Indian granite sources often have reactive silica. Combined with high-alkali cement (sometimes 0.8-1.0% Na₂O eq), AAR causes cracking over 5-15 years. Cheap — almost no one is still alive who remembers specifying AAR tests for 1980s construction. Test per IS 2386 Part 7 Annex A for any project in AAR-susceptible regions (test takes 14 days).
5. Buying 'IS 383 compliant' without supplier test certificates. Aggregate suppliers often claim IS 383 compliance without actually testing. Ask for: (a) sieve analysis per IS 2386 Part 1, (b) specific gravity per IS 2386 Part 3, (c) silt/clay content per IS 2386 Part 2, (d) AAR per IS 2386 Part 7 if in susceptible region. Archive these per delivery batch. If supplier cannot provide, test yourself; if refuses tests, change supplier.
IS 383:2016 is the current code; a significant improvement over the 1970 edition it replaced. Amendment No. 1 (2019) clarified M-sand testing; Amendment No. 2 (2023) added recycled aggregate provisions in Annex C.
River sand mining restrictions have dramatically changed the Indian aggregate market. Tamil Nadu, Karnataka, and Maharashtra have banned or restricted river sand extraction. M-sand supply now accounts for 50-70% of fine aggregate in these states. Most good M-sand supplies meet Zone II; some manufacturers (VSI crushers with washing) produce Zone III or blended sands.
Quality variance: Primary-mill M-sand (VSI-crushed, washed, graded) consistently meets IS 383. Cottage-scale M-sand from small jaw-crushers often has excessive fines (>15% passing 150 μm) and high silt content — rejected for structural concrete. Always ask for supplier credentials and test results before opening a volume contract.
Cost implications: M-sand costs 10-15% more than river sand (where available). The cement content may increase 3-5% for M-sand mixes because angular particles have higher water demand. Net per-m³ cost is similar or 5% higher for M-sand. For projects in sand-restricted states, there is no alternative — specify M-sand per IS 383:2016 from day one.
For high-performance concrete (M60+), specific gravity and grading consistency become critical. Source-approval testing from a single approved quarry is mandatory; mixing batches from different quarries for the same pour introduces variability that invalidates mix design.
| Parameter | IS Value | International | Source |
|---|---|---|---|
| Fine Aggregate Grading - % Passing 600 µm Sieve (IS 383 Zone II) | 60-79% | 50-85% | ASTM C33/C33M Table 1 (Fine Aggregate Grading) |
| Fine Aggregate Fineness Modulus | 2.50-3.10 (typical for Zone II, derived from grading) | 2.3-3.1 (general requirement) | ASTM C33/C33M |
| Los Angeles Abrasion Value (Coarse Aggregate, max % loss) | 50% (for concrete other than wearing surfaces, Table 2) | 50% (for concrete subject to abrasion, Table 1) | ASTM C33/C33M |
| Clay Lumps and Friable Particles (Coarse Aggregate, max % by mass) | 1.0% (Table 3) | 3.0% (Table 1) | ASTM C33/C33M |
| Soundness (Magnesium Sulfate, Coarse Aggregate, max % loss) | 18% (Clause 7.2 referencing IS 2386 Part 5) | 18% (Table 1) | ASTM C33/C33M |
| Coal and Lignite (Coarse Aggregate, max % by mass) | 1.0% (Table 3) | 1.0% (Table 1, for concrete where surface appearance is important) | ASTM C33/C33M |