Cyclic shear test of a geosynthetic clay liner for a secondary containment application

摘要

ABSTRACT: This note presents the results of a cyclic shear test of a secondary containment linernsystem composed of sand/GCL/sand. The GCL was a needle-punch-reinforced wovenonwovennproduct with a thin geomembrane laminated to the nonwoven side. Under a normal stress ofn100 kPa, shearing occurred at the sand/geomembrane interface and the GCL sustained no visiblendamage after 25 cycles of loading with a displacement amplitude of 20 mm and a frequency ofn1 Hz. Material property tests performed on pre-cyclic and post-cyclic GCL samples providednadditional evidence that the GCL specimen did not sustain damage due to cyclic loading. Analysisnof the cyclic loading data indicates hysteretic stress-displacement behavior that is broadly similar tonnatural soils and displays strength and stiffness degradation as well as reduction in damping rationwith continued cycling.