Product Standards for Silica Densifiers

1. Implementation standards

GB8076-2008 “Concrete Admixtures”

JGJ/T70-2009 “Standard for Basic Performance Test Methods of Building Mortars”

JC474-2008 “Mortar, Concrete Waterproofing Agent”

2. Product characteristics

(1) Impermeability: It has high impermeability, and the anti-permeability index of concrete mixed with this product It can be increased by 2 to 4 times to reach P8-P30.

(2) Frost resistance: It can significantly improve the frost resistance of concrete. The elastic modulus of 200 freeze-thaw cycles is greater than 70%.

(3) Compactness: It can significantly improve the resistance of concrete to the intrusion and erosion of harmful ions (chloride ions, sulfate ions, etc.).

(4) Safety: low chloride ion content, no corrosion or rust to steel bars.

(5) Environmental protection: non-toxic, harmless, and safe for health and the environment.

3. Scope of application

(1) Key projects such as railway bridges, tunnels, overpasses, roads, and airport buildings.

(2) Crack resistance and waterproofing of concrete used in tunnel linings, culvert frame structures, buildings and underground waterproofing projects.

(3) The cast-in-place concrete track bed slabs, concrete bases, concrete caps, bridge piers and other concrete structures of ballastless tracks are impermeable and dense.

4. Main performance indicators

5. Usage methods and precautions

(1) Add directly to the mortar or concrete mixer, and the mixing time will be longer than normal mixing. 30 to 60 seconds, counted as 2 and a half minutes or 3 minutes.

(2) The concrete mix proportion design is the same as that of ordinary concrete, but the cement dosage should not be less than 300kg/m3.

(3) Use fresh but not expired Portland or ordinary Portland cement. The cement has good activity and stability. The cement grade is generally P·O 32.5 or P·O 42.5.

(4) Sand and stone should be well graded, contain little mud and comply with relevant regulations.

(5) The concrete must be vibrated and compacted without sliding vibration or strong vibration, and the concrete and mortar must be compacted and compacted.

(6) Mortar or concrete should be covered with wet straw bags in time to strengthen moist curing. The general curing time is not less than 7-14 days. Concrete curing agents can also be used for curing.

6. Packaging, storage and transportation

Powders are packed in double-layer composite bags with a net weight of 30kg/bag and a shelf life of 12 months. They should be protected from direct sunlight and moisture-proof. Store on pallets off the ground in a dry and ventilated room.

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