Development of a Treatment Strategy Applicable to Field Conditions for the Repair of Vertical Fractures in Concrete Using MICP

Concrete plays a vital role in infrastructure and is often exposed to harsh conditions. Reducing the permeability of damaged concrete through durable repairs is crucial to prevent further deterioration. This study develops a Microbially Induced Calcite Precipitation (MICP) treatment for field conditions, targeting millimeter-scale, vertical fractures with limited access. Treatment used three injection ports while ultrasonic and representative permeability measurements characterized crack evolution. After treatment, the crack permeability decreased significantly, and the treated block showed a repair tensile strength of 0.5 MPa compared to the original concrete's 2 MPa. SEM-EDS analysis revealed a well-distributed, strongly cemented repair interface. The study demonstrates that MICP can effectively seal vertical fractures, providing a durable, low-permeability repair suitable for field conditions.