In order to study the durability of solidified waste mud, dry-wet cycle experiments were carried out under the erosion of sodium chloride solutions with different concentrations. The unconfined compressive strength and mass change rate of solidified mud were studied and analyzed. The results show that when the number of dry-wet cycles increases, the unconfined compressive strength and mass of the sample show a downward trend. The unconfined compressive strength of the solidified mud in 40 g / L sodium chloride solution decreases the most, reaching 52.89%, and the mass loss reaches 8.36 g. The microstructure analysis was carried out by scanning electron microscopy. It was found that the hydration products such as hydrated calcium silicate gel ( C-S-H ) and calcium hydroxide crystal ( C-H ) in the solidified mud samples under the coupling of chloride erosion and dry-wet cycle were reduced, and more pores and cracks appeared. Under the same number of dry-wet cycles, the higher the concentration of sodium chloride solution, the more serious the micro-damage inside the sample. The decrease of the strength of the solidified slurry is due to the hydrolysis of the hydration products in the solidified mud under the combined action of chloride salt and dry-wet cycle, and some of the materials are dissolved, resulting in more cracks.

Embankments and foundation geotechnical structures are frequently subjected to long-term cyclic loading due to traffic during their service life. Excessive cumulative deformation can lead to pavement cracking and uneven settlement of the subgrade. This study conducts a series of dynamic triaxial tests to analyze the effects of the number of cycles (N), effective confining pressure (sigma(c)), and dynamic stress amplitude (sigma(d)) on the axial cumulative strain (epsilon(d)) characteristics of solidified mud samples. Additionally, it investigates the evolution model of epsilon(d) of solidified mud and establishes a predictive model for this strain. In conjunction with the NMR tests, this research further investigates the effects of sigma(c) and sigma(d) on the pore distribution of solidified mud after loading. Ultimately, the correlation between microscopic pore structure indicators and epsilon(d) is elucidated. The results indicate that the epsilon(d) behavior of solidified mud under cyclic loading exhibits characteristics of plastic shakedown. Furthermore, the exponential hyperbolic function model more accurately characterizes the relationship between epsilon(d) of the samples and N. Before and after cyclic loading, the micropores of the samples accounted for over 95 % of the total pore volume, predominantly concentrated in the radius range of r < 0.3 mu m. A correlation exists between the average pore size of the sample and epsilon(d), which is primarily influenced by sigma(d) and sigma(c).