Alkali-free Concrete Accelerator is a new, high-performance product developed with new materials. It is compatible with many cements.
Features and Advantages of Accelerating Admixtures
(1) Homogeneity : This is a clear, colorless liquid. It has good homogeneity.
(2) Lower dosage : The recommended dose is between 3% and 8% of cement mass. Cement concrete sets and hardens rapidly, and both the initial and the final setting time is short.
Good durability. Because the alkali free concrete accelerator admixture doesn’t contain as much alkali, like the alkaline accelerations, the concrete is less likely to be damaged by the addition of these substances.
The alkali free cement accelerater contains no alkaline cations, is neutral or mildly acidic and does not corrode the skin or health of construction workers. The alkalifree accelerator is able to reduce the dust and amount of rebound that occurs during the spraying procedure, greatly improving the construction site.
Small Rebound Rate: According to experience, the rebound rate for alkali free accelerating admixtures used in spraying is below 15%. Use of alkali free accelerating admixtures reduces the amount of waste material and labor and equipment needed to clean up the waste. The benefits are clear.
The difference between strength. The alkali free accelerator admixtures exhibit high early strength with a low late strength loss. Alkali-free accelerations used to increase the support strength reduce the amount and cracking of cement.
(7) High adaptability, suitable for cements of different types in the range 3%-8%
It has no negative effect on concrete durability. It is non-chloride and has no adverse effect on the durability of concrete.
(9) Spraying reduces waste and protects workers’ health by preventing dust.
Hardened concrete is compact and impervious, and it can be mixed with shotcrete of high strength.
Use accelerator in concrete
Alkali free liquid concrete accelerator suitable for shotcrete construction, leak plugging and ground Cement concrete rapid Construction, concrete emergency rescue and repair works, and concrete reinforcement.
Attention needed when using concrete accelerator
(1) Dosage The dosage of alkali free liquid accelerator depends upon the temperature of concrete, the base and environment as well the activity of cement and the setting time. The recommended dosage for alkali-free liquid concrete accelerator depends on the temperature of the concrete, the environment and the base as well as the activity and setting time of the cement used.
(2) Process for dry spraying : the concrete is first mixed, then the liquid concrete accelerator (alkali-free) is added through the metering nozzle to the water. Finally, the concrete is sprayed with water.
(3) The wet spraying method is the following: the concrete is pre-mixed with water and then the liquid concrete accelerator is added to the compressed air through the metering nozzle.
In these situations, it is important to pay attention to the precise dosage of the additive. Concrete’s best water-cement proportion is =0.45. If the water-cement proportion is low, even small amounts of alkali free liquid concrete accelerater can produce better results. The water-cement ratio >0.5 will cause the concrete to take longer to set up and decrease the strength at the beginning.
(5) The alkali free liquid accelerator adapts well to concrete’s consistency, and is ideal for shotcrete that has a high slump (>200mm).
(6) If you use a higher dosage than what is recommended, the coagulation will be too slow and the strength will drop early, which will affect the adhesion and structure of the product.
(7) Prior to using the alkali free liquid concrete accelerater, the metering pumps, pumping liquids (filters) and accelerator pipeline must all be soaked in water. To prevent clogging, it is necessary to clean the pump system daily.
Storage of concrete Accelerator
The alkalifree Cement Accelerator comes in plastic barrels that can be packed according to customer needs.
Plastic buckets need to be handled with caution so that they don’t break.
Store it in an airtight container in a cool place that is dry and ventilated, avoid moisture and keep the temperature between 5 and 35.
Concrete accelerater must not be stored in metal containers. Before using the product, stir it well to prevent precipitation.
Shelf life of concrete Accelerator
When stored in an original airtight container, liquid accelerator has a shelf life of 6 months.
Safety instructions for concrete accelerator
Wearing safety goggles or gloves and other precautions is recommended. The alkali-free accelerator must be applied with safety.
If skin is contacted, immediately rinse the area with water. In the event of contact, immediately rinse with water.
If swallowed: Drink lots of water and immediately go to the hospital.