Abstract: Fissure grouting is a general method in the fissure reinforcement field in earthen sites. The expansibility of slurry and the mechanical compatibility between concretion and site soil are the key factors on whether the grouting measures can fulfill the role of sealing and bonding. The swelling and fluidity tests of SH-(CaO+F+C) slurry with nine different mix ratios and water cement ratios, and three different water-cement ratio slurries of the mixture ratio CaO:F:C = 3:2:5 were selected as optimum slurry. The best curing age was determined by the concretion strength test with continuous interval age. And then the thermal expansion coefficient of the grout concretion and the site soil were obtained by the thermal expansion test and the unconsolidated undrained triaxial test. The failure modes, stress-strain curves, shear strength parameters and elastic modulus of three kinds of specimens, which are grout concretion, grout concretion - remolded site soil and remolded site soil were also obtained. The results show that the thermal expansion coefficient of grout concretion and site soils are the same in magnitude. The mechanical behavior of three kinds of grout concretion and remolded site soil are consistent. Among them, the grout concretion with a mixture ratio of CaO:F:C = 3:2:5 and the water-cement ratio of 0.50 has the best mechanical compatibility with the remolded site soil.

Key words: earthen sites, quick lime, triaxial sheer test, failure mode, stress-strain relations, mechanical compatibility