Performance of laboratory geogrid-reinforced retaining walls under freeze-thaw cycles

To investigate the effects of freeze-thaw cycles on performance of geosynthetic reinforced earth retaining walls, two model tests of 1.0 m-high geogrid-reinforced retaining (GRR) walls without and with the loading plate and 10 kPa surcharge were carried out under five freeze-thaw cycles. In each freeze-thaw cycle, both freeze-temperature of −15°C and thaw-temperature of 35°C were maintained for 12 h alternatively. The test results showed that the temperature field and mechanical performance of the GRR walls significantly depended on the ambient temperature and the number of the freeze-thaw cycles. The effect of ambient temperature on the temperature field in the model GRR walls gradually reduced with the distance from boundary increase, which is more obvious for the model GRR wall with the loading plate. The settlement at the top of the model walls and the lateral displacement increased with the increase of the number of freeze-thaw cycles, especially for the model wall with a surcharge. The additional earth pressures and geogrid strains in the model GRR walls significantly varied with the ambient temperature. The test results also showed that the performance change of GRR walls mainly happened in the initial two to three freeze-thaw cycles.