When micro-expansive agent is added to concrete, what proportion is it usually added?

The recommended dosage is 8 ~ 12%, and the dosage should be appropriately increased when preparing post-cast strip and reinforced concrete with post-cast strip. Self-waterproof technology can be adopted in the prepared concrete, which integrates the building structure and waterproof function, eliminates external waterproof and makes the building structure simpler.

The mixing time of concrete mixed with expansive agent is 30 seconds longer than that of ordinary concrete, the concrete temperature should be lower than 30℃, the free falling distance of concrete should be controlled within 2 meters when pouring, and the vibration should be uniform and dense, and no vibration leakage, under vibration and over vibration are allowed. The concrete prepared by expansive agent can adopt seamless design and construction technology of super-long reinforced concrete, and can also be used for post-pouring zone treatment of ordinary concrete.

Extended data

Precautions:

1, the current mixing station or mixing station must be fed according to the determined proportion of shrinkage-compensating concrete, the metering device must be accurate, and the expansion agent cannot be added less, otherwise it can't meet the requirements of shrinkage compensation, but it can't be added too much, otherwise it will damage the concrete structure.

2. Pay attention to the secondary plastering before the final set of concrete mixed with expansion agent to prevent the appearance of surface shrinkage cracks.

3. After concrete pouring with expansive agent, the basement should be backfilled with lime soil as soon as possible, and the roof should be waterproof and insulated as soon as possible.

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