Abstract:With the rapid development of the lithium salt industry, the accumulation of lithium slag is also increasing. In order to promote the comprehensive utilization method of lithium slag, lithium slag is used as an admixture on the cement composite soil without side limit compressive strength and three-axis compression test. Lithium slag dosage on the cement composite soil compressive strength, stress-strain, shear strength, cohesion and internal friction angle of cement composite soil were analyzed. Moreover, the mechanism of action of lithium slag on the mechanical properties of cement composite soil was analyzed by using the SEM method. The results show that when the amount of lithium slag is 12%, the unconfined compressive strength of cement composite soil is increased by 85.1% compared with 0% of lithium slag. The stress-strain relationship curve of lithium slag cement composite soil shows a softening type. The brittleness becomes more apparent with the increase amount of lithium slag and the shear strength, cohesion and internal friction angle increase in direct proportion to the amount of lithium slag doped within a certain range. With the increase of confining pressure, its ductility becomes more obvious. The SEM test results show that lithium slag can improve the internal structure of cement composite soil and enhance its compactness. The experimental results provide certain technical parameters and theoretical references for the design and construction of lithium slag in cement composite soil.