Portland cement additive early-strength shrinkage-reducing agent

This is a kind of dry power material (referred to as concrete early-strength shrinkage-reducing agent) which is added to Portland cement-based mortar, concrete and products to improve early and late strength and reduce the volume shrinkage, and the code is CQJSJ.

Technical requirements

1 Chemical component:

1.1 The content of chlorine ion

The content of chlorine ion in the concrete early-strength shrinkage-reducing agent shall not be more than 0.06 %.

1.2 The content of alkali

The content of alkali in the concrete early-strength shrinkage-reducing agent is represented with the calculated value of Na2O+0.658K2O and shall not be more than 0.5 %.

 Physical and mechanical property indexes

Note: the mixing amount of early-strength shrinkage-reducing agent is to replace the cement in the datum cement mortar directly

Technical characteristics

1. Improve the early strength and the mould turnover rate, reduce the steam-curing temperature or shorten the steam-curing time, and improve the production efficiency.

2. Improve the late strength, and the 28d strength can be increased by 5-30%.

3. Have the micro expansion performance so as to compensate shrinkage, reduce the shrinkage of concrete and improve the anti-cracking ability.

4. Without requirement on early strength, adding the early-strength shrinkage-reducing agent can sharply reduce the mixing amount of Portland cement and lower the cost of concrete.

5. The mass concrete with low cement, low adhesive material, high grade and low hydration heat can still be prepared when properly reducing the dosage of Portland cement, which may reduce the cost of concrete, reduce the hydration heat of high-grade mass concrete, reduce the temperature difference between the core temperature and surface temperature of the concrete and also reduce the cracking.

6. Improve the frost resistance

7. Improve the anti-permeability

Scope of application

1. The early-strength shrinkage-reducing agent A is mainly applied to:

1.1、Premixed commodity concrete

Adding a small amount of early-strength shrinkage-reducing agent A can reduce the dosage of Portland cement in the concrete, reduce the cost of concrete; reduce the dry shrinkage, thus reducing the cracking; and reduce the carbon emission during the application of concrete.

1.2. The mass concrete with low cement, low adhesive material, high grade and low cost

   Adding properly proportioned early-strength shrinkage-reducing agent A can prepare mass concrete with low cement, low adhesive material, high grade and low hydration heat while properly reducing the dosage of Portland cement, which may reduce the cost of concrete; reduce the hydration heat of high-grade mass concrete, reduce the temperature difference between the core temperature and surface temperature of the concrete and also reduce the cracking.

1.3. Improve the durability of the concrete and prepare concrete and concrete products with high quality.

1.4. Use sand gravel aggregates with low quality to prepare the high performance concrete.

1.5. Use solid wastes and construction wastes to prepare the high performance concrete.

2. The early-strength shrinkage-reducing agent B is mainly applied to:

2.1. Prepare concrete members by composite application of Portland cement with the proper proportion can reduce the steam-curing temperature, energy consumption and the emission; or shorten the steam-curing time under the condition of not reducing the steam-curing temperature, quicken the mould turnover and improve the production efficiency.

2.2. When the mixing amount of early-strength shrinkage-reducing agent is high, the concrete members can still reach demoulding strength after 8~10 hours, which can cancel the steam-curing, save the energy consumption and reduce the emission.

2.3. Reduce the shrinkage and cracking of the concrete.