Research on workability, mechanics, and durability of cementitious grout: A critical review

Abstract

Good workability, mechanical behavior, and durability are the prerequisites for the application of cementitious grout in engineering fields. To further promote the application of cementitious grout in the field of civil engineering, the research status of cementitious grout from the aspects of workability, mechanical behavior, and durability were systematically reviewed in this study, and future research directions and trends were predicted and analyzed. It is shown that the reasonable addition of supplementary cementitious materials, chemical admixtures, and fibers can improve the workability, mechanical behavior, or durability of cementitious grout. However, further research is needed on the mix proportion of cementitious grout that balances workability, mechanical behavior, and durability. Numerous studies have examined the constitutive behavior of cementitious grout under uniaxial compression. The results show that compared to ordinary concrete, cementitious grout exhibits a larger peak strain, smaller elastic modulus, larger proportional limit, and more obvious brittle characteristics. However, research is urgently needed on the constitutive behavior of cementitious grout under dynamic, repeated load or multi-axis and other complex stress states, as well as the constitutive behavior of cementitious grout constrained by stirrups. Corresponding theoretical or semi-theoretical constitutive models still need to be established. In terms of durability, cementitious grout shows better frost resistance and resistance to penetration of harmful ions than concrete due to the hardened slurry of cementitious grout having a more compact pore structure. The performance degradation of cementitious grout under freeze-thaw, and salt corrosion has been explored, but further research is needed on the degradation mechanism, as well as the ion diffusion coefficient model and ion transport model. In addition, cementitious grout may be subjected to multiple ion erosion or coupling effects of multiple factors during actual service, and thus, research on the durability of cementitious grout under the above-mentioned environmental coupling effects still needs to be carried out.