MONITORING THE TRIGGERING OF LIQUEFACTION USING IMAGE PROCESSING

Abstract

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