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The retaining wall with reinforced soil is exposed to various types of loads, including static active earth pressure caused by the self-weight of the backfill soil, seismic loads due to earthquakes, vehicle/railroad loads, and cyclic loads induced by seasonal temperature changes causing contraction/expansion. To ensure the internal stability of the retaining wall, the pullout resistance of the installed geogrid must be secured. This study presents the pullout load test results for a geogrid installed in sandy soil under cyclic loading, either in displacement-controlled or load-controlled conditions. In the pullout tests, factors such as the frequency, amplitude, and number of cycles of the pullout load were varied to consider various cyclic loading characteristics. The trends in the maximum pullout resistance and the initial pullout stiffness were analyzed. The analysis showed that under displacement-controlled cyclic loading, as the amplitude increased, both the pullout resistance and stiffness significantly decreased, with the degree of decrease intensifying as the displacement amplitude increased. This trend was also observed in the analysis of changes in pullout stiffness under cyclic loading. On the other hand, under load-controlled cyclic loading, the pullout resistance and cumulative pullout displacement both tended to decrease as the frequency increased over a fixed period, while the pullout resistance decreased and the cumulative displacement increased as the amplitude increased.

来源平台：JOURNAL OF THE KOREAN GEOSYNTHETIC SOCIETY