EFFECT OF IRREGULAR TIME-HISTORY ON THE CYCLIC RESISTANCE OF SAND
Abstract
The liquefaction behaviors of sandy soils are
generally investigated using stress or strain controlled dynamic tests in the
laboratory. In terms of ease and
applicability of analysis, uniform loading patterns are usually preferred.
However, irregular wave forms with different amplitudes and frequencies are
generated throughout the soil layers during seismic excitations. In this study,
a comprehensive series of cyclic tests have been performed on clean sand samples.
Conventional uniform loading and ground-motion records scaled to different
cyclic stress ratios were applied to identically prepared specimens. The pore
pressure build-up and accumulated strain effects are investigated regarding the
effect of the loading type and cyclic stress ratio. The outcome of test series
aimed to provide further improvement on dynamic strength approaches for
liquefaction assessment, in order to expand its use in current engineering
practice.
Keywords
Dynamic Triaxial Test,Irregular Loading,Sand Particles,Excess Pore Water Pressure
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