In the first of a regular feature, the IGS Young Members Committee will be publishing summaries of previous IGS Student Award Papers. For this edition, “The Effect of Reinforcement Position on Geogrid Reinforced Clay Liners” was selected from the 3rd African Regional Conference On Geosynthetics (GeoAfrica 2017).
Marx and Jacobsz presented a paper on geogrid reinforced clay liners and won the student award competition at GeoAfrica 2017. This paper presents an interesting experimental investigation to understand the effect of reinforcement position on the response of geogrid reinforced clay liners subjected to differential settlements. The differential settlements below the landfill liner can result in distortion and crack for the liners. In this study, centrifuge modeling tests were conducted for three cases including, unreinforced, bottom-reinforced, and top-reinforced clay liners, to investigate the effects of geogrid reinforcement and the optimized position of reinforcement to reduce the cracks. Innovation methods were used for measurements and interpretation of test results, including laser scanner to identify the crack locations on the clay liner surface and digital image velocimetry to calculate the strain in the clay liner. Cracks were observed for all three cases subjected to a central settlement of 1.5 m; however, the cracks for the unreinforced and bottom-reinforced liners were significantly more severe than for the top-reinforced linear. For the unreinforced liner, the crack extended from the top surface to the based, while the cracks stopped at the position of geogrid reinforcement for both the bottom-reinforced and top-reinforced liners. Results indicate that top-reinforced clay liner is more effective than bottom-reinforced liner on reducing the cracks due to differential settlements.
To read the full paper, click here.
– Reported by Yewei Zheng, IGS Young Members Chair for the North American Region.