Experimental Investigations on the Pull-Out Behavior of Tire Strips Reinforced Sands

Abstract

Waste tires have excellent mechanical performance and have been used as reinforcing material in geotechnical engineering; however, their interface properties are poorly understood. To further our knowledge, this paper examines the pull-out characteristics of waste tire strips in a compacted sand, together with uniaxial and biaxial geogrids also tested under the same conditions. The analysis of the results shows that the interlocking effect and pull-out resistance between the tire strip and the sand is very strong and significantly higher than that of the geogrids. In the early stages of the pull-out test, the resistance is mainly provided by the front portion of the embedded tire strips, as the pull-out test continues, more and more of the areas towards the end of the tire strips are mobilized, showing a progressive failure mechanism. The deformations are proportional to the frictional resistance between the tire-sand interface, and increase as the normal stresses increase. Tire strips of different wear intensities were tested and presented different pull-out resistances; however, the pull-out resistance mobilization patterns were generally similar. The pull-out resistance values obtained show that rubber reinforcement can provide much higher pull-out forces than the geogrid reinforcements tested here, showing that waste tires are an excellent alternative as a reinforcing system, regardless of the environmental advantages.

DEM investigation of shear mobilisation during tyre strip pull-out test

“…The results also indicate that higher normal stress can extend the critical pull-out displacement corresponding to the peak pull-out force. Overall, although the values for pull-out forces in numerical simulations are quite small as shown in Figure 7(a), these general trends are consistent with the experimental findings reported by Li et al (Li et al,2017) shown in Figure 5 plotted by Li et al (2017) was measured in kN/m and it was normalized by the width of the box for comparison. Some interaction between neighbouring tyre strips may affect the result, hence the pull-out force may not be simply divided by a factor of three, and the exact effect of tyre length will be presented later in this paper.…”

“…It was concluded that the ultimate pull-out capacity of cell-type waste tyres was about 1.25 times larger than that of geocells. Li et al (2017) found that the pull-out loads mobilised by tyre strips were two times higher than the pull-out loads mobilised by the uniaxial and biaxial geogrids, under the same pull-out testing conditions. Additional recent studies (Li et al, 2016;Li et al, 2020;Li et al, 2021) also revealed a good potential of using larger-size waste tyres to partially or completely replace geogrids or geocells.…”

Experimental study on the interface characteristics of geogrid-reinforced gravelly soil based on pull-out tests

“…In addition, they recommended that pull-out tests be performed at a low normal stress. Li et al 12 conducted a series of pull-out tests to investigate and compare the load‒displacement characteristics of tire belts and uniaxial and biaxial geogrid-reinforced sandy soils under different normal stresses. The damage to the tire belt-reinforced sand was progressive, with the shear strength of each part of the sand depending on that of various other parts of the sand.…”

Effective Length Prediction and Pullout Design of Geosynthetic Strips Based on Pullout Resistance

“…Additional studies have been conducted on the shear resistance of reinforced soil and on interactions using mixed soil [ 33 , 34 , 35 ]. Grid-type reinforcement has been used in many studies, but studies on the pullout behavior of geosynthetic strips have been conducted to extend the applicability of geosynthetic strips [ 27 , 28 , 36 , 37 ].…”