Related Experiment Video
Updated: Jun 21, 2025

Sandy Soil Improvement through Microbially Induced Calcite Precipitation MICP by Immersion
Published on: September 12, 2019
Experimental Study on the Crack Concrete Repaired via Enzyme-Induced Calcium Carbonate Precipitation (EICP)
Gang Li1, Deqiang Yan1, Jia Liu1
1Shaanxi Key Laboratory of Safety and Durability of Concrete Structures, Xijing University, Xi'an 710123, China.
Abstract:
A low-carbon and environmentally friendly EICP method for repairing concrete cracks is presented to prolong the service life of concrete. In this study, we took concrete as the research object and quartz sand as the filling medium and employed the EICP injection method to repair concrete cracks. The internal repair effect of EICP on concrete cracks was evaluated with a combination of ultrasonic and compressive strength tests. The concrete repair mechanism of EICP was identified with a combination of EDS, XRD, and SEM tests. The results indicate that with an increase in the fracture depth, the ultrasonic sound time of the crack specimen increased gradually, and the ultrasonic wave transit time value of the crack specimen decreased significantly after EICP repair. After repair, the compressive strength rose. The highest compressive-strength recovery rate of a 0.3 mm wide specimen is 98.41%. The calcium carbonate crystal formed using EICP is vaterite. The probability density function model of the Laplace distribution was constructed, which showed good applicability and consistency in the ultrasonic sound time and compressive strength measured via experiments. The formed calcium carbonate crystals can be tightly and evenly attached to the cracks with the EICP injection repair method, resulting in a better repair effect.
Related Concept Videos
Microcracking in Concrete
Corrosion of Reinforcement
However, over time and under certain conditions like carbonation, chloride ingress, and cracking this protective state can be compromised. Steel has areas with...
Acid Attack on Concrete
The rate at which hydrogen...
Carbonation Shrinkage
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction...
Sulfate Attack on Concrete
Sulfates from sources like soil, groundwater, or industrial effluents...
Effect of Sea Water on Concrete
Concrete in areas between tide marks,...

