Numerical Simulation of the Working Mechanism of Denti-Geogrid Reinforcement

To explore the working mechanism of retaining a wall reinforced with denti-geogrids, the numerical simulation of a pullout test was performed, the working behavior and influencing factors were analyzed, a generalized model was suggested, and an ultimate pullout force calculation formula was proposed. The research obtains the following results. (1) The horizontal displacement of the inner segment of the geogrid is relatively small because of the denti-strips. (2) The displacement gradients of the denti-geogrid are evidently large, whereas the horizontal displacement core is approximately 25 cm outside the denti-strip. The peak value of the horizontal displacement is approximately 3 cm. (3) The pullout force peaks when the denti-strip is approximately 3 m from the lateral boundary. The effective span is extended, and the resistance of the denti-strip increases with denti-strip spacing. Denti-strip height is positively correlated with the pullout force, whereas the influence of thickness is insignificant. (4) The working mechanism of denti-geogrid can be roughly described by three processes, namely, compaction, detour flow, and convergence. (5) The calculation values of the ultimate pullout force obtained from the generalized model are close to the numerical test results. Thus, the applicability of the suggested model was verified.