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BC-AME(II) Magnesium Oxide Expansive Agent

Brief Introduction

BC-AME(II) magnesium oxide expansive agent is an expansive clinker with light-burned MgO as the main mineral component. It features adjustable expansion initiation time, expansion rate, expansion termination time and expansion magnitude. It is applicable to structures such as side walls, bottom slabs and roof slabs that require crack resistance and impermeability. It can compensate for the temperature drop shrinkage of mass concrete and is suitable for crack control of hydraulic mass concrete structures.

Product Features

· Stable Expansion Products: Magnesium hydroxide (Mg(OH)₂) formed by MgO hydration has extremely low solubility and is highly stable in natural environments. Once the MgO hydration reaction is completed, the expansion deformation ceases. It will neither cause unlimited expansion nor retraction, ensuring stable long-term performance.

· Excellent Crack and Impermeability Resistance: The micro-expansion effect of BC-AME(II) can effectively compensate for shrinkage, improve concrete compactness, increase the ultimate tensile value of concrete, and achieve the purpose of crack resistance and impermeability. Concrete mixed with 6% BC-AME(II) can reach an impermeability grade of P10 or higher.

· Superior Durability: BC-AME(II) has low alkali content and chloride ion content, which will not cause durability problems such as alkali-aggregate reaction (AAR) and steel bar corrosion. Moreover, through the expansion-induced self-compaction effect, it can further increase concrete compactness and enhance its durability.

· High Expansion Efficiency: The 90-day expansion rate of concrete mixed with HME®-I can reach 90×10⁻⁶~120×10⁻⁶, and the expansion gradually stabilizes from 90 days to 180 days.

Technical Data

The performance indicators of BC-AME(II) comply with the technical requirements of the association standard CBMF 19-2017 Magnesium Oxide Expansive Agent for Concrete.

Test Item	Restrained Expansion Rate Index	Restrained Expansion Rate Index	Restrained Expansion Rate Index
Activity Value	35s~99s (Type R)	100s~199s (Type M)	200s~300s (Type S)
7d in Water at 20℃, ≥	0.022	0.015	0.015
Δε (Expansion Increment) in Water at 20℃, ≥	0.022	0.017	0.010
7d in Water at 40℃, ≥	0.045	0.035	0.025
Δε (Expansion Increment) in Water at 40℃, ≥	0.025	0.030	0.040

Usage Method and Precautions

· Recommended Dosage: The common dosage is 4%~8% of the total mass of cementitious materials. The maximum dosage shall be determined through soundness test demonstration according to actual engineering conditions. The optimal dosage shall be determined by on-site tests based on raw material conditions, ambient temperature and construction requirements.

· Concrete Mixing: BC-AME(II) shall be added into the mixer together with cement, sand and aggregates. It shall not be pre-dissolved in water. The mixing time shall be appropriately extended, generally by about 30 seconds.

· Concrete Curing: After concrete pouring is completed, it shall be covered and cured in a timely manner and shall not be exposed to direct sunlight.

Packaging and Storage

· Packaging: BC-AME(II) is available in paper-plastic composite bags or bulk tankers for convenient loading, unloading and transportation. The net weight is 40kg per bag, and custom packaging is also available according to customer requirements.

· Storage: BC-AME(II) shall be stored in a sealed, dry and cool place with a shelf life of 6 months.

Safety Precautions

· BC-AME(II) is non-toxic, non-irritating, non-radioactive, non-flammable and non-explosive. It contains no formaldehyde and is environmentally friendly.

· For your personal safety, always wear protective gloves and safety goggles during handling and use of BC-AME(II) to avoid direct skin contact. In case of accidental eye or skin contact, rinse immediately with plenty of clean water. Seek medical attention promptly if irritation persists.