Magnesium Oxide Expansion Agent
TC-MS
Magnesium oxide expansive agent is a novel product developed based on the principle of micro-expansion to compensate for concrete shrinkage. Made with MgO as the primary expansion source, supplemented by active mineral materials, this product exhibits controlled, delayed micro-expansion and deformation properties, compensating for chemical, drying, and thermal shrinkage of concrete. The expansion duration matches the concrete's shrinkage rate, effectively preventing concrete cracking and water seepage, improving concrete durability, and meeting concrete's crack resistance and anti-seepage requirements.
Applications: Widely used in crack-resistant and anti-seepage concrete projects for civil and industrial buildings and special structures, such as basements, pools, water towers, underground passages, subways, and underground pipeline corridors; as well as large-scale water conservancy, nuclear power, petroleum, and railway projects.
Implementation Standard: CBMF 19-2017 "Magnesium Oxide Expansion Agent for Concrete"TC-MS Magnesium Oxide Expansion Agent Technical Specifications
Test items | Technical indicators |
R-type | Type M | S-type |
Magnesium oxide content/% | ≥80.0 |
Loss on ignition/% | ≤4.0 |
Moisture content/% | ≤0.3 |
Reaction time/s | <100 | ≥100 and <200 | ≥200 and <300 |
Alkali content/% (Na20 +0.658K20) | ≤0.75 |
Fineness | 80μm square hole sieve residue/% | ≤5.0 |
1.18mm square hole sieve residue/% | ≤0.5 |
Limit expansion rate/% | 7 days in 20℃ water | ≥0.020 | ≥0.015 | ≥0.015 |
In 20℃ water, Δξ | ≥0.020 | ≥0.015 | ≥0.010 |
7 days in 40℃ water | ≥0.040 | ≥0.030 | ≥0.020 |
In 40℃ water, Δξ | ≥0.020 | ≥0.030 | ≥0.040 |
Coagulation time/min | Initial condensation | ≥45 |
Final Setting | ≤600 |
Compressive strength/MPa | 7d | ≥22.5 |
28d | ≥42.5 |
