Mac Accelerator DS

DESCRIPTION
MAC ACCELERATOR DS is an alkali-free powder accelerator formulated to provide set
acceleration in DRY Shotcrete, while reducing the safety hazards associated with traditional
alkaline shotcrete accelerators. It allows spraying to take place even on wet surfaces subject
to slight infiltration.
USES & ADVANTAGES
MAC ACCELERATOR DS is suitable for use with shotcrete in tunnels, mines, and for slope
stabilisation etc.
Useful in areas of application such as:
 Tunnels and galleries
 Securing rock-faces
 Embankment and excavations
 Thin section concrete shells
 Concrete repair-work
 Strengthening concrete structures
Advantages include:
 Quick setting.
 Early-age strength development, excellent long-term strength and durability.
 High resistance to carbonation.
 Reducing water permeability.
 Very low dust production.
 Alkali-free and non-toxic, which eliminates any adverse effects from additional alkali’s
in the spray dust.
 Minimum strength loss in the accelerated concrete.
 No additional surface and ground water pollution by leached out alkalis.
 Improves bond of shotcrete to rock and concrete, making overhead spraying easier.
 Non corrosive to steel reinforcement.
 Improves safety and non-toxic.
 Better adhesion.
 Reduced rebound.

PROPERTIES
Appearance: Off-White
pH Value (10% w/w in water): Approx. 4.0 ± 1.0
Bulk Density: Approx. 1000 ± 200 Kg/m3
Chloride Content (Cl-
): <0.01% STANDARDS Confirms to IS 9103-1999 (reaffirmed 2004) edition 2.2 (2007-2008), ASTM C494/C494-08a, Type C, BS 934 and EFNARC specification of sprayed concrete. APPLICATION The correct dosage must be determined by preliminary testing. For layer thicknesses of up to 15 cm in one pass, dosage is between 3% and 8% of weight of binder. Actual dosage has to be finalised on the basis of concrete trials. Overdosing may result in decreased strength. The dosage depends on temperatures, reactivity of cement used, required thickness of layers, setting time and early strength development required. It is preferable to use concrete with cement contents of no less than 400 kg/m3 for high early strength. MAC ACCELERATOR DS can be sensitive to different types of cement. It is suggested to use 100% clinker Portland cement for earlier setting time. During wet-mix spraying, the w/c ratio should be below 0.5 (preferably below 0.45) to achieve better results. The water content in aggregate must be taken into account in the calculation of water-cement ratio. PACKAGING MAC ACCELERATOR DS is supplied in 25 kg inner lined HDPE bags STORAGE & SHELF LIFE MAC ACCELERATOR DS should be stored in a dry environment in tightly closed original bags away from moisture contact. In original unopened bags shelf-life is up to 6 months. Presence of moisture causes the product to form lumps and reduces the performance. Consume the product within 6 hours after opening the bag. HEALTH & SAFETY Wear rubber gloves and goggles to avoid eye and skin contact. If contact occurs, clean with plenty of water. In case of eye contact, seek medical advice.