End-of-Life Tire Geocells for Unpaved Road Reinforcement: A Comparative Performance Assessment Under Cyclic Loading

The growing generation of end-of-life tires and the structural deficiencies of tertiary road networks in developing regions represent two interconnected challenges that call for integrated engineering solutions. Although recycled tire geocells have been explored as a reinforcement alternative for unpaved roads, their mechanical performance has not been systematically compared against conventional high-density polyethylene (HDPE) geocells under controlled cyclic loading, nor has the material valorization potential been quantified in terms of waste diversion capacity. This study systematically evaluates and compares the deformation response, stress distribution, and aggregate degradation of both systems through large-scale laboratory testing. An instrumented steel chamber was used to apply up to 100,000 load cycles at 600 kPa contact pressure, across two cell heights (150 mm and 200 mm) and two granular infill qualities. The 200 mm recycled tire geocell reduced permanent surface deformation by up to 84% relative to the unreinforced condition, and Traffic Benefit Ratio values reached up to 1.6 times those recorded for HDPE geocells under lower-quality infill. The viscoelastic response of rubber promoted energy dissipation and limited aggregate particle breakage. Confinement performance was fully preserved after surface reconditioning, confirming the durability of the reinforcement system under maintenance cycles. The fabrication process requires no chemical transformation, valorizing approximately 16 end-of-life tires per square meter—equivalent to 56,000 tires per kilometer of reinforced road. These findings support the large-scale valorization of end-of-life tires as functional geotechnical materials, offering a circular economy pathway for solid waste diversion in regions where both road infrastructure deficits and tire disposal challenges coexist.