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Cement Concrete — Design Mix (IS 10262:2019) • All Grades

Cement Concrete — Design Mix (IS 10262:2019) — All Grades

Full design-mix workflow for any grade (M10–M40+) — target mean strength, w/c limits (IS 456 Table‑5), water content (slump/agg size), FA zone, CA/FA split, admixtures, SSD→as‑received corrections, and a printable batch sheet. Nominal‑mix mode has been removed.

Standards used: IS 10262:2019 (mix design) + IS 456:2000 (durability: max w/c, min cement). Values here are starting estimates; confirm by lab/site trials.

Performance Targets

Good control (IS 10262). Auto-fills by grade; editable.
Non‑entrained typical ≈ 2%
Cannot exceed durability limit; pick per strength data/trials.
Water‑reduction is applied to baseline water content.

Materials (SSD unless noted)

Method snapshot (why these numbers?)

  1. Target mean strength: f′t = fck + 1.65·s (IS 10262).
  2. Pick target w/c (user) and check ≤ durability limit from IS 456 Table‑5 (by exposure & type).
  3. Water content from IS 10262 baseline (50 mm slump): 10 mm → 208 kg, 20 mm → 186 kg, 40 mm → 165 kg; adjust ±3% per 25 mm slump; apply water‑reducer %.
  4. Cement = Water / (w/c); if below minimum cement (Table‑5), bump cement and report revised w/c.
  5. Absolute‑volume method: V = 1 − (Vc + Vw + Vadm + Vair). Split V into CA/FA by Table base (Zone II, 20 mm at w/c 0.5 = 0.62) + corrections: ±0.01 per Δ(0.05) in w/c; size ±0.05 for 10/40 mm; zone offset (I: −0.02, III: +0.02, IV: +0.04). Convert to SSD masses via SGs.
  6. Moisture/absorption corrections: as‑received masses = SSD·(1+free%); batch water = water + Σ(Abs% − Free%)·mass.
Design Mix Concrete Calculator IS 10262:2019 Online Tool
IS 10262:2019 • IS 456:2000

Design Mix Concrete Calculator (IS 10262:2019) — How It Works & How To Use It

A practical, code-aware tool that designs concrete mixes for any grade using IS 10262:2019, checks IS 456 durability limits, and outputs a moisture-corrected batch sheet.

Design Mix Concrete Calculator (IS 10262:2019) — featured image
Contents
  1. What this calculator does
  2. Inputs you’ll need
  3. How it works (under the hood)
  4. How to use it
  5. Worked example (per 1 m³)
  6. Mini project (6.0 m³ slab)
  7. Assumptions & standards
  8. Jargon buster

What this calculator does (in plain English)

This tool designs concrete mix proportions for any grade (M10–M60+) using IS 10262:2019 and checks IS 456:2000 durability rules (max w/c and min cement). You enter engineering targets and material properties; the output is a per-m³ design mix plus a batch sheet with moisture corrections for FA/CA and the correct water to add.

Final mixes must be validated by trial batches for your materials, admixtures, and on-site workability.

Inputs you’ll need

  • Performance: Grade (fck), slump, nominal max aggregate size (10/20/40 mm), FA grading zone (I–IV), RCC/PCC, exposure class, target w/c.
  • Materials: Specific gravity (cement/FA/CA), FA/CA absorption (%) and free moisture (%).
  • Admixture (optional): Plasticizer/superplasticizer and dose (L/100 kg cement).

How it works (under the hood)

  1. Target mean strength — f′t = fck + 1.65 × s (IS 10262).
  2. Durability limits — IS 456 Table-5 caps w/c and enforces min cement for each Exposure × RCC/PCC combo.
  3. Water content — Baseline at 50 mm slump: 10 mm → 208 kg/m³, 20 mm → 186 kg/m³, 40 mm → 165 kg/m³; adjust ±3% per 25 mm, then apply water-reducer %.
  4. Cement & w/c — Cement = Water / (w/c); if below min cement, bump cement and recalc w/c (lower).
  5. Absolute volume — Subtract volumes of cement, water, admixture, air; split remaining aggregate between CA/FA. Base CA fraction ≈ 0.62 at w/c=0.50, 20 mm, Zone II; adjust ≈ ±0.01 per 0.05 change in w/c and small zone/size offsets.
  6. SSD → as-received — Convert to SSD masses with SGs. As-received = SSD × (1 + free moisture). Water to add = SSD water ± Σ(Abs − Free)·mass.
  7. Batch sheet & flags — Per-m³ cement (kg & bags), water to add (L), admixture (L), FA/CA as-received (kg), with quick checks for w/c and cement limits.

How to use it

  1. Pick Grade, RCC/PCC, Exposure, slump, NMA, and FA zone.
  2. Accept or tweak the suggested standard deviation for your quality control.
  3. Enter a target w/c (the tool will clamp to the IS 456 limit).
  4. (Optional) Choose admixture and dose.
  5. Enter SG, absorption and free moisture for FA/CA.
  6. Click Calculate → read per-m³ mix (SSD & as-received) and moisture-corrected water.
  7. Multiply by your wet volume for job quantities.
  8. Click Generate HTML Report to save a printable, step-by-step design sheet.

Worked example (per 1 m³)

Inputs: Grade M30 (fck=30 MPa), RCC, Moderate exposure, slump 100 mm, 20 mm NMA, FA Zone II, target w/c=0.45, air=2%, s=5.0 MPa, superplasticizer 20% cut @ 0.8 L/100 kg; SG: cement 3.15, FA 2.65, CA 2.70; Absorption: FA 1.0%, CA 0.5%; Free moisture: FA 2.0%, CA 0.2%.

38.25 MPa

Target mean strength f′t

0.45

w/c (used)

157.73 L

SSD water

350.51 kg

Cement (7.01 bags)

Step-by-step math (highlights)

  • f′t: 30 + 1.65×5.0 = 38.25 MPa.
  • Water: Base 20 mm @50 mm = 186 kg → +6% for 100 mm slump = 197.16 kg → 20% cut = 157.73 kg (≈ L).
  • Cement: 157.73 / 0.45 = 350.51 kg (≥ 300 min for RCC-Moderate).
  • Volumes: Vw=0.15773 m³; Vc=350.51/(3.15×1000)=0.11127 m³; Vadm=0.00280 m³; Vair=0.02 m³ ⇒ Vagg=0.70820 m³.
  • CA/FA split: base CA 0.62 @ w/c 0.50 → +0.01 for 0.45 ⇒ CA=0.63; VCA=0.44616 m³; VFA=0.26203 m³.
  • SSD masses: CA=0.44616×2.70×1000=1204.64 kg; FA=0.26203×2.65×1000=694.39 kg.
  • Moisture correction: FA (1.0–2.0)%=−6.94 L; CA (0.5–0.2)%=+3.61 L → net −3.33 L.
  • Water to add: 157.73 + (−3.33) = 154.40 L.
  • As-received: FA=694.39×1.02=708.27 kg; CA=1204.64×1.002=1207.05 kg. Admixture=0.8×(350.51/100)=2.80 L.

Mini project example — 6.0 m³ slab

Geometry5.0 m × 8.0 m × 0.150 m = 6.00 m³
Cement350.51 × 6 = 2,103 kg (~42.1 bags)
Water to add154.40 × 6 = 926 L
Sand (as-received)708.27 × 6 = 4,250 kg
Coarse aggregate (as-received)1207.05 × 6 = 7,242 kg
Admixture2.80 × 6 = 16.8 L

Consider a 5–10% logistics/handling buffer where appropriate.

Assumptions & standards

  • Standards: IS 10262:2019 (mix design), IS 456:2000 (durability: max w/c, min cement).
  • Water density 1 kg/L; air content default 2% (non-air-entrained).
  • Baseline waters: 208/186/165 kg/m³ for 10/20/40 mm at 50 mm slump; ±3% per 25 mm change.
  • CA fraction model: base 0.62 at w/c 0.50, Zone II, 20 mm; ≈ ±0.01 per 0.05 change in w/c; small zone/size offsets.
  • Trial mixes are mandatory before adoption.

Jargon buster

fck
Characteristic compressive strength at 28 days (e.g., M30 → 30 MPa).
f′t
Target mean strength = fck + 1.65·s.
w/c
Water–cement ratio by mass (e.g., 0.45). Lower → higher strength/durability.
Slump
Workability measure in mm.
NMA
Nominal maximum aggregate size (10/20/40 mm).
FA / CA
Fine aggregate (sand) / Coarse aggregate (stone).
SSD
Saturated-surface-dry reference state for aggregates.
Free moisture
Surface water carried into the mix by aggregates (reduces water you add).
Absorption
Water aggregates take up from the mix (increases water you add).
Specific gravity (SG)
Relative density vs water (cement ≈ 3.15; sand ≈ 2.65).

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