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1. Understand CSA expansion agent

High-efficiency CSA bulking agents are obtained by mixing a suitable natural hard rock with a special clinker consisting mainly of calcium sulfoaluminate and CaO. CSA expansion agents are always mixed with ordinary cement. When mixed with ordinary cement in the proper proportions and hydrated, CSA mortar or concrete swells in the early stages of hydration. This expansion, when restricted, minimizes drying shrinkage. Furthermore, its high expansion qualities make it ideal for use in prestressed concrete when the ratio of shrinkage reducing admixture to ordinary cement is increased.

CSA expansion agent can improve the sulfate resistance of concrete and does not pollute the water. High-efficiency shrink-reducing admixtures are being used in various areas of the construction sector and by various concrete product manufacturers. CSA expansion agent should be stored in a dry place and be protected from moisture.

2. What are the characteristics of CSA expansion agent?

CSA expansion agents should be mixed with Portland cement in varying proportions from 6% to 10% to function during the hydration process to minimize dry shrinkage of the concrete. Prevents shrinkage and cracking during heat of hydration; increases the impermeability of concrete. The characteristics of the CSA-based expansion agent are: 1. High capacity expansion efficiency; 2. Short-term stable expansion stage; 3. Low reliability of later water replenishment; 4. Low alkalinity.

Features of high-efficiency CSA expansion agent: 1. Low alkalinity. The alkali content of the high-efficiency CSA expansion agent is very low (R20<0.3%), which is beneficial to avoid AAR in calcium aluminate concrete. Short-term stable expansion phase. The stable expansion period does not exceed 14 days and does not affect the ultimate strength of concrete. 2. Less dosage and strong expansion ability. The general dosage of high-efficiency CSA expansion agent is 6 to 8% of the weight of ordinary cement, which is lower than other expansion agents such as UEA and CEA (the dosage is about 10 to 12% of the weight of cement) in the market.

The characteristics of using high-efficiency CSA expansion agent are to prevent cracking due to drying shrinkage and hydration heat. Increase the water tightness of concrete, so it can be used for building waterproofing. Ability to manufacture high-strength concrete products by chemical prestressing.

3. What are the applications of CSA expansion agent?

CSA expansion agent is used in structural self-waterproofing construction. Effectively prevent concrete cracking or leakage. CSA expansion agent is used to extend the space length of the cast-in-place super-long structure after the casting. CSA expansion agent controls cracks caused by temperature differences in large-scale structural concrete. CSA expansion agents are applied to rigid roofs. CSA expansion agent makes non-shrinking cement CSA.