Seismic response of retaining walls with cohesive backfill: Centrifuge model studies

Abstract

a b s t r a c tObservations from recent earthquakes show that retaining structures with non-liquefiable backfills perform extremely well; in fact, damage or failures related to seismic earth pressures are rare. The seismic response of a 6-m-high braced basement and a 6-m free-standing cantilever wall retaining a compacted low plasticity clay was studied in a series of centrifuge tests. The models were built at a 1/36 scale and instrumented with accelerometers, strain gages and pressure sensors to monitor their response. The experimental data show that the seismic earth pressure on walls increases linearly with the free-field PGA and that the earth pressures increase approximately linearly with depth, where the resultant acts near 0.33 H above the footing as opposed to 0.5-0.6 H, which is suggested by most current design methods. The current data suggest that traditional limit equilibrium methods yield overly conservative earth pressures in areas with ground accelerations up to 0.4g.

A finite element performance-based approach to correlate movement of a rigid retaining wall with seismic earth pressure

“…In the FE simulation, the values of the Rayleigh parameters  and  are computed for a critical viscous damping ratio (say 3% or 5%) for which the frequency of the system will be between the first two natural circular frequencies z1 and z2 . It is important to note that the ω ω Rayleigh damping formulation is based on the first two modes of the natural frequency of the soilretaining wall system because the response of the retaining walls is usually governed by their first two modes of vibrations [23]. [23] reported that over 97% of the total displacement of a retaining wall is captured in the first and second modes of vibration, while only about 3% of the total displacement comes from the third mode of vibration.…”

“…It is important to note that the ω ω Rayleigh damping formulation is based on the first two modes of the natural frequency of the soilretaining wall system because the response of the retaining walls is usually governed by their first two modes of vibrations [23]. [23] reported that over 97% of the total displacement of a retaining wall is captured in the first and second modes of vibration, while only about 3% of the total displacement comes from the third mode of vibration. ABAQUS [54] has been used to determine the natural circular frequencies of the first two modes of vibration for the soil-retaining wall system.…”

“…In this method, the effect of the earthquake is simulated by introducing additional forces called as the seismic inertia forces on to a soil wedge which exert lateral earth pressure on the retaining wall, called as the seismic earth pressure. Over the past many years, many researchers like [14][15][16][17][18][19][20] have modified and extended the MO method to propose new analytical solutions like the pseudo-dynamic method to compute the seismic earth pressure while other researchers like [21][22][23][24] developed experimental and numerical methods to compute the seismic earth pressure by using the MO method. Further, [25,26] have developed numerical methods for studying the phasing issues for the seismic response of yielding and non-yielding gravity retaining walls.…”

Younan-Veletsos retaining wall: The exact solution

“…Moreover, there is a lack of consensus both on how to define the earthquake acceleration, and how to consider backfill heterogeneity. In spite of these issues, these methods enjoy wide use to this day and seem to provide satisfactory 3 design for peak ground acceleration (PGA) as high as 0.4 g [9].…”

Solitary Wave Generation and Propagation under Hypergravity Fields

“…Hence, centrifuge experiments are frequently used in the laboratory to study the actual behaviors of prototype models. For example, Brennan et al [19] studied the strength reduction in the upheaval buckling of buried pipes, Baziar et al [20] investigated the responses of underground tunnels to rupture reverse faults, and Candia et al [21] discussed the response of a retaining wall to seismic activity. In addition, centrifuge experiments have been developed to study water-soil interactions (e.g., the research on submarine landslides presented by Coulter and Phillips [22], Coulter [23], and Gue [24]).…”