Dynamic Properties of PAYTEX-Polymer-Treated Sand Reinforced with Waste Tire Textile Fibers

The instability of the sand particles has always been an inevitable obstacle in geotechnical engineering and their stabilization by additives is an effective method. This study investigates the shear modulus and damping ratio of sand treated with a polymeric liquid and reinforced by fibers using cyclic triaxial tests. For sand modification, a polymeric liquid called PAYTEX-NL25 with dosages of 1, 2, 3, and 4% of soil dry weight, and for reinforcement, a recycled tire fiber as 2% of soil dry weight was used. The cyclic triaxial tests were conducted with a confining pressure of 100 kPa and cyclic stress ratios (CSR) of 0.1, 0.2, and 0.4 up to 200 cycles. The results showed that in stabilized samples with polymer, the two mentioned parameters stayed unchanged up to 200 cycles due to the bond’s high strength, and the increment of polymer to 4% increased the shear modulus. The polymer increase to 2% decreased the damping ratio of non-contained fiber specimens followed by a stable trend afterward. In reinforced samples with fibers, a 1% polymer addition resulted in a damping increase, and up to 4% reached a constant status. Moreover, polymer-modified sand reinforcement reduced the shear modulus and increased the damping ratio.