Study on the intelligent protection of cement-based materials through the synergistic action of lactate intercalated double metal hydroxides and microorganisms

The effective protection of cement-based materials in marine environments was an important way to enhance the durability of marine engineering structures. In this study, the feasibility of integrating bimetallic hydroxides with microorganisms as an intelligent protection effect for cracked cement-based materials was fully demonstrated. Firstly, the calcination method was utilized to prepare double metal hydroxides with lactate intercalated layers (MgAl-LDHs-C3H5O3−). Simultaneously, systematic characterization of the prepared MgAl-LDHs-C3H5O3− was conducted, confirming the successful intercalation of inter layer ions. Secondly, the fixing capacity of MgAl-LDHs-C3H5O3− for erosive ions was tested in a simulated aqueous environment. The experimental findings demonstrated that through ion exchange, the fixation rate of SO42− reached 100 %, while that of Cl− reached 44 %. Meanwhile, C3H5O3− was exchanged into the solution system. The MgAl-LDH-C3H5O3− immobilized with erosive ions were subjected to comprehensive characterization. The outcomes unveiled a thorough elucidation of the mechanism underlying the fixation of erosive ions by MgAl-LDH-C3H5O3−. Finally, the microorganisms were cultured in a simulated solution system. The results showed that C3H5O3− exchanged into the solution was decomposed and utilized by microorganisms. A significant quantity of CaCO3 produced through microbial mineralization was identified. Based on the experimental results, it could be inferred that the combination of MgAl-LDH-C3H5O3− with microorganisms played a role in ion immobilization and mineralization improving. This study provided new insights into the intelligent protection of cracked cement-based materials in marine environments. •The protective properties of cementitious materials were enhanced by the synergistic action of bimetallic hydroxides and microorganisms.•Layered bimetallic hydroxides with lactate inserts were synthesized to inhibit corrosion.•Mineralization by microorganisms was enhanced due to the introduction of bimetallic hydroxides.