Numerical study on the influence of creep behavior of geosynthetic reinforcements on the mechanical behavior of reinforced soil bridge abutments

<p indent="0mm">Numerical simulation is a widely adopted method for predicting the performance of geosynthetic-reinforced soil (GRS) abutments. In current studies, geosynthetic reinforcement materials are typically modeled as linear elastic with constant tensile stiffness derived from constant rate-of-strain (CRS) tensile tests. However, many common geosynthetic materials exhibit significant creep behavior under practical engineering tensile conditions, which can substantially affect the mechanical behavior of reinforced soil structures. This paper employs the finite difference method to simulate GRS abutments, incorporating reinforcement modeled with constant stiffness that neglects creep, as well as both constant and nonlinear stiffness that account for creep behavior. The influence of creep characteristics on the service performance of the abutments is examined. The simulation results reveal that GRS abutments modeled with nonlinear stiffness considering creep demonstrate mechanical behavior comparable to those with constant stiffness that also accounts for creep, though the latter exhibits slightly greater deformations and reinforcement strains. In contrast, the deformations and strains calculated using constant stiffness from CRS tests are significantly lower than those in the scenarios that incorporate creep, with the discrepancy increasing as the load intensifies. Notably, the tensile force in the reinforcement modeled with CRS-derived stiffness is higher than in the other two scenarios. For the HDPE geogrid widely used for GRS abutments in the field, the reduction factor for the required tensile strength due to creep is approximately 1.2, this value remains relatively stable under varying service load conditions.