In Europe, concrete admixtures are tested to EN 934-2; in China, to GB 8076. Both compare a test concrete with a control concrete and set limits for water reduction, setting and strength. This page explains how a calcium lignosulfonate water reducer is tested under each.
Identity
| Item | Detail |
|---|---|
| Name | Calcium lignosulfonate (calcium lignosulphonate) |
| CAS | 8061-52-7 |
| Nature | Sulfonated lignin polymer from sulfite pulping, polydisperse |
| Form | Powder or 45% solution |
EN 934-2
| EN 934-2 category | Water reduction vs control |
|---|---|
| Table 2: water reducing / plasticizing | At least 5% |
| Table 3.1: high range water reducing / superplasticizing | At least 12% |
A calcium lignosulfonate admixture is normally tested in the Table 2 category. The GAC-CaLS-Construction TDS gives up to 12% water reduction at 0.20–0.30% by weight of cement, so a trial is needed to show the margin over 5% in the reference concrete. Check the current edition for the full list of requirements.
GB 8076
GB 8076 groups water reducers into ordinary, high-efficiency and high-performance classes, each with accelerating, standard or retarding types. Calcium lignosulfonate is tested as an ordinary water reducer. The test concrete is compared with a reference concrete made with reference cement.
| Test item in GB 8076 | What it shows |
|---|---|
| Water-reducing ratio | Water saved at the same slump |
| Bleeding ratio | Bleed water vs reference concrete |
| Air content | Air added by the admixture |
| Setting time difference | Earlier or later set vs reference |
| Compressive strength ratio | Strength vs reference at set ages |
| Shrinkage ratio | Drying shrinkage vs reference |
Use the current edition of GB 8076 for the limit of each item and type.
Preparing for Either Test
- Choose the grade and dose from the TDS range.
- Formulate the admixture and fix its solids content.
- Test in the reference concrete of the standard, against the control.
- Record water reduction, set, strength and air, and compare with the limits.
Grade Data
| Parameter | Construction Grade (GAC-CaLS-Construction), TDS Rev. 2.0 |
|---|---|
| Form | Light brown powder |
| Bulk density | 0.8 g/cm³ |
| Moisture | 5% max |
| pH (5% solution) | 4–6 |
| Recommended dosage | 0.20–0.30% by weight of cement; higher dosages may retard set beyond specified limits |
| Water-demand reduction | Up to 12% |
| Packaging | 25 kg woven bags with PE liner; 500 kg or 600 kg jumbo bags |
| Shelf life | 12 months |
Typical values from the current TDS. Each lot ships with a COA.
Frequently Asked Questions
What does EN 934-2 require of a water reducer?
A water-reducing admixture (Table 2) must reduce water demand by at least 5% against the control mix. A high-range water reducer (Table 3.1) needs at least 12%.
What is GB 8076?
The Chinese national standard for concrete admixtures. It covers ordinary water reducers (accelerating, standard and retarding types), high-efficiency and high-performance water reducers, among others.
Which GB 8076 category fits calcium lignosulfonate?
Ordinary water reducer, standard or retarding type, depending on its effect on setting time in the test.
What is the CAS number of calcium lignosulfonate?
CAS 8061-52-7. It is a sulfonated lignin polymer of varying molecular size, not a single compound.
Samples and Documents
Send the cement type, mix design, target slump or setting time, and the test standard you work to, to info@greenagrochem.com or use the contact form.
Related: ASTM C494 Type A and D · water reducing agent dosage · all construction uses
