Experimental Investigations on Pullout Behavior of HDPE Geogrid under Static and Dynamic Loading

Abstract

This paper describes a series of laboratory pullout tests that were performed to investigate the pullout behavior of high-density polyethylene (HDPE) uniaxial geogrid subjected to static and dynamic loading. Pullout tests were conducted on HDPE geogrid reinforced coarse sand under normal static loading (60–300 kPa), dynamic loading with different amplitudes (20, 40, and 60 kPa), and different frequencies (2, 4, and 6 Hz) by using the newly developed pullout apparatus. The results indicated that the pullout resistance of geogrid presented different growth patterns with the increase of normal loads under static loading. The amplitude and frequency both had significant effects on the interaction between reinforcement and soil, and the increment of the pullout resistance was 0.6 kN and 0.3 kN, respectively. The effect of dynamic loading on the soil-geogrid interface can be gradually equivalent to that of static loading corresponding to the balance position of dynamic loading with the increase of frequency compared with the static loading. The results of this study are helpful for the selection of the strength of the reinforcement in different locations and to simplify the study on the stress of reinforcement in reinforced soil structures under traffic loads.

Comparison between uniaxial and pull-out tests setup for polyester and HDPE geogrids

“…The specimens' failure mode of GG1 and GG2 tested with serrated steel-lined clamps and plastic-lined clamps, respectively, (Figure 5) was in good agreement with the guidelines of ASTM D6637 stating that specimen slippage outside the clamp or fracturing inside the clamp is not acceptable. Figure 6a shows the stressstrain curve obtained from testing GG1 with serrated steel-lined clamps where the uniaxial tensile strength equals 82 kN/m and the in-isolation secant stiffness at 2% strain equals 1100 kN/m, which agreed with the literature where the secant stiffness at 2% strain for HDPE geogrids with tensile strength 80 ± 20 kN/m ranged between 865 kN/m and 1750 kN/m [13,16,[19][20]. Figure 6b shows the results of testing GG2 with serrated steel-lined clamps and plastic-lined clamps where the uniaxial tensile strength reached 55 kN/m and 80 kN/m, respectively, indicating a reduction of 31% when it was tested with serrated steel-lined clamps.…”

Effects of freeze-thaw cycles on the tensile properties of geogrids and shear behavior of geogrid-soil interface

“…The test results showed that the normal cyclic load frequency and amplitude dramatically influenced the interface shear stress. In case of the interface characteristics between distinct backfill materials such as gravel or clay and geogrids, Zuo et al [10] performed pull-out and direct shear tests of geogrids in sand-gravel, cohesive soils, and ballast. They reported a relatively low shear strength for the interface between the geogrid and clay, whereas the interface with sand-gravel and ballast exhibited high shear strength.…”

Evaluation of the Effectiveness of Geogrids Manufactured from Recycled Plastics for Slope Stabilization—A Case Study

“…Efforts to use recycled plastics in the manufacture of geogrids are supported by numerous studies that emphasize the feasibility and environmental benefits of this practice [ 40 , 41 , 42 ]. Therefore, recent advances in geogrid technology represent an important step towards improving slope stabilization techniques in geotechnical engineering [ 43 , 44 , 45 , 46 , 47 ]. These advancements refer not only to the incorporation of new materials, but also to the adoption of innovative manufacturing techniques.…”