CSA expansive agent is a special calcium sulfoaluminate cement additive. CSA expansive agent has an expansive rate (about 6-8% than ordinary cement). Its main active ingredients are calcium sulfoaluminate and calcium oxide. CSA expansive agent is designed to be mixed with ordinary cement as a concrete admixture. CSA expansive agent can minimize the dry shrinkage of concrete, and can generate self-stress (0.2~0.7mpa) when restrained to prevent cracking and waterproof.
Strong CSA expansive agent is used as a part of cement, and its ratio to ordinary Portland cement depends on the intended use and degree of restraint. It is usually 6%-8% of the weight of ordinary cement, which is relatively low compared with other expansive agents. Strong CSA expansive agent and ordinary cement must be fully and evenly mixed with aggregate and water in a mechanical mixer, and the mixing time is slightly longer than ordinary concrete.
CSA expansive agent can be added to concrete or mixed with ordinary cement, as shown below: railways, tunnels, cracks and waterproof layers of high-rise buildings; surface automatic waterproofing, impermeable mortar, moisture-resistant mortar, etc.
1. CSA expansive agent can help concrete have faster slump loss and shorter setting time;
2. CSA expansive agent can set the self-stress of 0.2~0.7mpa in the concrete admixture;
3. CSA expansive agent has no obvious influence on concrete strength;
4. The early strength of concrete using CSA expansive agent is higher than that of other expansive agents;
5. CSA expansive agent greatly improves the impermeability of concrete, and the impermeability index reaches above S30;
6. CSA expansive agent greatly improves the frost resistance and corrosion resistance of concrete;
7. CSA expansive agent compensates the drying shrinkage of concrete and prevents concrete from cracking.