Case Background
In a concrete structure repair project for a client in India, traditional cement-based repair mortars suffered from high brittleness, poor durability, and insufficient crack resistance, failing to meet long-term usage requirements. The client purchased redispersible polymer powder from our company, Micome Chemical, to address these issues.
Application Plan
Material Selection
Cement
Fine aggregate: Quartz sand with a mesh size of 80-200.
Redispersible polymer powder: Mikrant 4035N
Other additives: Polycarboxylate superplasticizer.
Construction Process
Mix cement, sand, superplasticizer, and polymer powder in proportion and place them in a mixer to ensure thorough and uniform mixing.
Prepare the mortar mixture according to standard specifications, controlling the flowability.
Apply the mixed mortar to the surface of the concrete structure to be repaired, adjusting the thickness according to actual needs.
Performance Improvement
Adhesive Strength
The tensile adhesive strength of the repair mortar significantly increased with the addition of redispersible polymer powder. However, there was an optimal dosage. Beyond a certain amount,
further addition of polymer powder did not significantly enhance the adhesive strength.
Flexural Strength
The flexural strength of the mortar initially increased and then decreased with the addition of
polymer powder. At the optimal dosage, the flexural strength reached its peak at 13.95 MPa.
Compressive Strength
The compressive strength decreased with increasing polymer powder dosage but remained
sufficient for practical use.
Flexibility and Durability
The addition of polymer powder reduced the mortar's brittleness and improved flexibility. It also significantly enhanced water resistance and durability.
Construction Performance
The polymer powder reduced the mortar's viscosity, improving workability and construction efficiency. It also extended the setting time, which was beneficial for repair operations.
Construction Results
After actual application, the repaired concrete structure had a smooth surface with no cracks or detachment. The mortar's durability and water resistance were significantly enhanced, meeting long-term usage requirements.
Conclusion
The addition of redispersible polymer powder significantly improved the adhesive strength, flexural strength, flexibility, and durability of the repair mortar while optimizing construction performance. This modified mortar is particularly suitable for concrete structure repair projects, effectively extending the service life of the structure.
