Effect of Shaking History on the Cone Penetration Resistance and Cyclic Strength of Saturated Sand

The effect of shaking history on cone penetration resistance, cyclic resistance ratio, and their correlation to each other for saturated sand is examined using centrifuge model tests. Prior laboratory and centrifuge modeling studies have shown strain history can have a strong effect on the cyclic strength of sand, but data describing how these effects track with cone penetration resistance are lacking. The effects of shaking history on cone penetration resistance and cyclic strength are investigated using centrifuge models of saturated Ottawa sand on a 1-m radius centrifuge with a 6-mm diameter cone penetrometer. The centrifuge models are subjected to a series of shaking events at progressively increasing amplitudes until liquefaction is triggered. This motion is repeated until the sand no longer liquefies. Cone penetration tests are performed before any shaking, after liquefaction is triggered, and after liquefaction no longer occurs. Inverse analyses of accelerometer array data are used to compute profiles of dynamic shear stresses and strains. The results are used to examine the effects of prior strain history on cone penetration resistance, cyclic resistance ratio, and their correlation to each other. The centrifuge test results are also compared with a case history-based liquefaction triggering correlation.