Sieve Analysis Report
Material: 20mm Nominal Size
| I.S. Sieve Designation | Wt. Of Sample retained (gms) | Cumm. Wt. Retained (gms) | Percentage Of Wt. retained (%) | Cumm. Percentage Of Wt. retained (%) | Percentage Of Wt. Passing | Prescribed Limit Passing (%) |
|---|---|---|---|---|---|---|
| 40 mm | 100.0 | 100 | ||||
| 20 mm | 92.1 | 85-100 | ||||
| 10 mm | 13.5 | 0-20 | ||||
| 4.75 mm | 4.9 | 0-5 | ||||
| Pan | 100.00 | 0.0 | -- | |||
| TOTAL | 0 | Weights and Percentages balanced | ||||
Material: 10mm Nominal Size
| I.S. Sieve Designation | Wt. Of Sample retained (gms) | Cumm. Wt. Retained (gms) | Percentage Of Wt. retained (%) | Cumm. Percentage Of Wt. retained (%) | Percentage Of Wt. Passing | Prescribed Limit Passing (%) |
|---|---|---|---|---|---|---|
| 12.5 mm | 100.0 | 100 | ||||
| 10 mm | 95.0 | 85-100 | ||||
| 4.75 mm | 12.0 | 0-20 | ||||
| 2.36 mm | 2.1 | 0-5 | ||||
| Pan | 100.00 | 0.0 | -- | |||
| TOTAL | 0 | Weights and Percentages balanced | ||||
Coarse Aggregate Gradation: 20mm & 10mm Sieve Analysis (IS 383:2016)
In the production of structural concrete, coarse aggregates make up the majority of the concrete's volume (roughly 60% to 75%). They are the primary load-bearing components in the matrix. If the gradation—the distribution of particle sizes—is incorrect, the concrete will suffer from severe workability issues, honeycombing, or an excessive demand for cement paste to fill the voids.
To prevent this, Quality Control (QC) engineers strictly monitor the gradation of coarse aggregates using a Sieve Analysis Test. This tool automates the calculations for the two most critical nominal sizes used in construction: 20mm and 10mm aggregates, ensuring they comply with the stringent limits of IS 383:2016.
1. Why Test 20mm and 10mm Separately?
In modern Ready Mix Concrete (RMC) batching plants and major site infrastructure projects (like canal linings and rigid pavements), coarse aggregate is rarely supplied as a pre-mixed, naturally graded material. Instead, it is supplied in single-sized fractions.
- CA1 (Coarse Aggregate 1): Typically the 20mm nominal size. It provides the bulk structure and mass.
- CA2 (Coarse Aggregate 2): Typically the 10mm nominal size. It acts as a filler material to occupy the large voids left between the 20mm particles.
By testing CA1 and CA2 separately, mix-design engineers can determine the exact blending ratio (for example, 60% of 20mm and 40% of 10mm) needed to achieve an ideal combined gradation curve. This blending minimizes void space, creating a denser, stronger, and more economical concrete mix.
2. Decoding the IS 383:2016 Gradation Limits
This calculator evaluates your field sample weights against the standard passing limits for single-sized aggregates. Here is what the specific limits represent in field conditions:
20mm Nominal Size Limits
40mm Sieve (100% Passing): Ensures there are no oversized boulders that could block concrete pump lines or get caught in heavy reinforcement.
10mm Sieve (0-20% Passing): Limits the amount of undersized material. Too much material passing the 10mm sieve means the supplier is mixing in cheaper, smaller aggregates, which increases the surface area and the water-cement ratio.
10mm Nominal Size Limits
12.5mm Sieve (100% Passing): Prevents oversized stones from infiltrating the 10mm stock, which would ruin the void-filling characteristics of the CA2 blend.
2.36mm Sieve (0-5% Passing): Strictly limits stone dust and grit. Excess micro-fines in the coarse aggregate bin will drastically increase the water demand of the concrete mix and reduce compressive strength.
3. The Mathematical Formulas Used
During the physical test, engineers place the oven-dried sample into a mechanical sieve shaker. After shaking, the weight of the material retained on each sieve is recorded. Our tool instantly processes these raw weights using the following sequential formulas:
- Percentage Retained (%) = (Weight Retained on Sieve / Total Sample Weight) × 100
- Cumulative Percentage Retained (%) = The sum of the Percentage Retained on that specific sieve PLUS all sieves above it.
- Percentage Passing (%) = 100 - Cumulative Percentage Retained
4. Quality Control Consequences
Failing to maintain these limits has severe structural and financial consequences on-site. If aggregates are consistently out of bounds (for example, retaining too much flaky or elongated material on the 10mm sieve), the workability of the concrete drops. Site supervisors are then tempted to add extra water to the transit mixer, fundamentally violating the water-cement ratio and destroying the structure's long-term durability and strength.
5. How to Use the Calculator
This automated calculation sheet speeds up daily TPI reporting and mix-design verifications:
- Ensure your field sample is properly quartered, oven-dried, and weighed. Input the Total Sample Weight (g) at the top of the tool (standard tests use 1000g, 2000g, or 5000g depending on the maximum nominal size).
- To manually input data, simply type the weight retained on each sieve. The tool will automatically compute the cumulative weights, percentages, and passing limits.
- To generate a theoretical report for simulation or formatting purposes, click Generate Data. This will populate both the 20mm and 10mm tables with randomized, IS 383-compliant values.
Disclaimer: This calculator is intended as a reporting aid and simulation tool for civil engineering professionals. It strictly follows IS 383:2016 gradation limits for single-sized aggregates. Always conduct physical laboratory weighments for actual site approvals.
