Assessment of Horizontal Seismic Coefficient for Three Different Types of Reinforced Soil Structure Using Physical and Analytical Modeling

Abstract

Pseudo-static analysis is one of the most common and simplest approaches used to assess the seismic stability of reinforced-soil retaining walls. Despite the importance of the equivalent seismic coefficient as the key parameter of the pseudo-static approach, no specified criterion has yet been provided for the selection of this coefficient. Therefore, in this study, an attempt was made to assess the horizontal seismic coefficient (kh) in three different types of reinforced soil structure based on the physical and analytical modeling. For this purpose, first, the values of yielding acceleration (ay), the axial force distribution along the reinforcements at the failure stage and the geometry of slip surfaces were determined in different conditions by the shaking table test. Then, by using the limit equilibrium horizontal slice method (HSM) and based on the results obtained from shaking table tests, the physical models were simulated to estimate the equivalent seismic coefficients needed to establish slip surfaces similar to those observed in the shaking table tests. Finally, according to the results obtained, the upper bound of the horizontal seismic coefficient for the steel-strip reinforced-soil wall (SSW), soil-nailed wall (SNW), and mechanically stabilized earth/soil nail hybrid retaining wall (HRW) were introduced as a function of peak ground acceleration (PGA) and was compared with existing design codes.