Vertical Pullout Test for Measurement of Soil-Geomembrane Interface Friction Parameters

摘要

This paper presents a vertical pullout test (VPT) developed to measure the peak interface friction angle (δ) and adhesion (a) between soil and planar geosynthetic products. The key advantages of this test are (1) relatively low capital cost for the equipment, (2) relatively simple compared to the conventional methods, (3) the setup can be relatively easily adapted by small conventional soil testing laboratories, and (4) the setup can be transported to the field for field measurement for relatively quick preliminary evaluation of soils. The testing method was evaluated by comparing the δ and a obtained from the VPT to (1) those parameters measured using a conventional soil direct shear apparatus modified to also measure interface friction between planar geomembranes and soil according to ASTM D5321-02, and (2) values published in the literature. Three coarse-grained soils and three types of geomembranes having three sample sizes were evaluated using the pullout test. The peak interface parameters obtained from the VPT were within 12 % of the values obtained from the direct shear test.