Seismic Response of Reduced Scale Soil Retaining Wall at Varying Backfill Density

Abstract

In this study, the shaking table tests on small scale model of soil retaining walls are done in the laboratory. The seismic response of three retaining wall models is studied by performing a series of laboratory experiments under the influence of changing backfill relative density by applying different acceleration amplitudes. The background of the study, literature on the study and attempted study is presented in detail. The small scale model construction, materials used, instrumentation and results are also presented in detail in this study. Three types of wall: rough, frictionless and rough with surcharge walls are constructed to different relative densities and these walls are tested at three different excitations. The static and dynamic displacement of these walls with the change in backfill relative densities is also recorded and presented in this study. The acceleration amplification comparison is also made between the base and top of the backfill densities of different retaining walls. It is observed that the dynamic displacement decreases with increase in relative density of backfill. The displacement in surcharge wall is recorded as maximum. The acceleration amplification increases with increase in relative density of backfill at higher acceleration amplitudes whereas it decreases with increase in relative density of backfill at lower excitation. The acceleration amplification is most pronounced in case of frictionless wall as compared to rough wall with and without surcharge. The displacement in frictionless wall is less than rough wall with surcharge but more than rough wall without surcharge. The results obtained from this study are helpful in understanding the relative performance of soil retaining walls constructed when subjected to higher base excitation for the range of relative density employed in the testing program.