MONITORING THE TRIGGERING OF LIQUEFACTION USING IMAGE PROCESSING

Abstract

In recent studies triggering or initiation of liquefaction is usually performed to characterize thepotential of the soil to liquefy. Its behavior before, during and after liquefaction in a laboratory test needs tobe understood. Image processing was implemented to monitor the triggering of liquefaction and estimate thecyclic shear strain that would trigger liquefaction. Lucas and Kanade pyramidal optical flow algorithm wereused to track the movement of the soil. A mirrorless camera was the instrument used. The strain-controlledconsolidated undrained cyclic triaxial test was performed. The loose condition was tested at 2.4, 1.6 and 0.8mm strain amplitudes. The confining pressures used were 50, 100 and 200 kPa. Based on the results, theestimated values for the cyclic shear strain that would trigger liquefaction had a range of values due to theoccurrence of non-homogeneous deformation. The minimum values were in agreement with the typicalvalues while the maximum values were larger. For the behavior of the soil before, during and afterliquefaction had occurred, the deformation behavior was different. More deformations were observed afterthe triggering of liquefaction.