Reduced-Scale Shake Table Testing of Seismic Behaviors of Slurry Cutoff Walls

Abstract

This paper presents a reduced-scale shake table test on the seismic responses of a section of soil-cement-bentonite (SCB) slurry cutoff wall. The geometric scale of slurry wall width was chosen as 1∶3 (model:prototype). A section of a slurry wall with dimensions of 150 cm long, 20 cm wide, and 160 cm tall was constructed and tested on a one-dimensional shake table. A 187 cm (long)×150 cm (wide)×180 cm (tall) steel-frame box was anchored on the shake table and contained the slurry wall and sandy soil that was compacted on both sides of the wall. Spring-supported wood panels were installed at the bottom and on two sides of the box to create a boundary that has the stiffness of dense sand. The slurry wall and the confining soil were instrumented with accelerometers, LVDT, linear potentiometers, and dynamic soil stress gauges to respectively record the accelerations, vertical and horizontal deformations of the wall, and transient dynamic soil pressures on the wall during the simulated seismic excitations. Dynamic scaling laws were implemented in the shake table testing to scale the seismic excitation. Two shake table tests were conducted using the 1997 Loma Prieta earthquake motions and sinusoidal sweep-frequency motions (from 0.2 to 6.0 Hz), respectively. The shake table tests provided a preliminary understanding of the seismic performances of the SCB slurry wall in levees and earthen dams.