Sensitivity Analysis of Road Actual Conditions to Evaluate the Optimal Positioning of Geogrid Using Finite Elements and Dynamic Methods

Roads are subjected to vehicle traffics with different loads and velocities. Geogrid reinforcement is of the best methods for road improvement due to the ease of construction, delay in damage development and financial efficiency. This study evaluates pavement response under different loads and velocities, before and after geogrid reinforcement. A finite element software (ABAQUS) is used for numerical modeling and the geogrid position in various depths is investigated. Field results of Pennsylvania are used for validation of the primary model. Results indicated that the positioning of geogrid is associated with the base layer thickness and the ratio of elasticity modulus of asphalt to the base layer. When the base layer thickness is increased, the optimal position of the geogrid will be changed from layers interface to the upper one-third of the base layer. Due to the geogrid impact, when the ratio of elasticity modulus of asphalt to the base layer is approximately equal to 4, the ratio of strains in these two layers becomes equivalent. For higher and lower elasticity modulus ratio values, the optimal position of geogrid is at the base layer bottom and asphalt layer bottom, respectively. Velocity and wheel weight parameters had no impact in this response.