Abstract: Current seismic design specifications for reinforced soil retaining walls primarily derive horizontal seismic coefficients from a limited set of model tests or numerical simulations, without considering the influence of facing type on acceleration amplification coefficient distribution. To address this gap, three sets of shaking table tests were conducted on reinforced soil retaining walls with different facing types, using identical soil and geosynthetic materials. The aim was to investigate the frequency-domain distribution of acceleration responses and the effect of facing type on the acceleration amplification coefficient. The test results show that the reinforcement materials significantly improves soil stiffness and integrity, enhancing the amplification of seismic wave components at both low and high frequencies. The acceleration amplification coefficient increases with height along the wall, and the facing type significantly influences its distribution. Specifically, for wrapped retaining wall with low facing stiffness, the acceleration amplification coefficient decreases as peak acceleration increases, reaching a maximum value of 1.69. In contrast, for modular and integral retaining walls with higher facing stiffness, the acceleration amplification coefficient increases with peak acceleration, reaching the maximum values of 1.84 and 1.37, respectively. Based on these findings, this paper proposes a method for calculating the horizontal seismic coefficients of reinforced soil retaining walls with different facing types using the quasi-static method. The results provide valuable insights for seismic stability analysis of reinforced soil retaining walls.

Key words: reinforced soil retaining wall, different facing types, shaking table test, horizontal seismic coefficient, seismic design