Modeling and Analysis of Infinite Beam on Extensible Geosynthetic-Reinforced Granular Fill-Soft Soil System Subjected to Moving Loads

摘要

In this paper modeling and analysis of an infinite beam (e.g. railway track), with an axle load moving with constant velocity is presented. The granular fill layer (ballast layer) is idealized as a Pasternak shear layer, which may contain a geosynthetic layer in between or at the interface overlying a soft soil stratum. The Geosynthetic is idealized by a rough membrane overlying a series of compressible Winkler springs representing the underlying soft soil, which responds identically in tension and compression. In the analysis the geosynthetic layer is assumed to be extensible, satisfying no slip and compatibility conditions at the interface between the reinforcement and the neighboring soil. This condition eliminates the two interfacial shear stress parameters and at the same time also incorporates the stiffness of geosynthetic in the model. It is observed that this approach results in substantial decrease in the predicted values of mobilized tension in the geosynthetic layer as compared to previous studies. It has been further observed that the flexural response of the beam as well as of the reinforcement, are greatly affected by the velocity, intensity of load and stiffness of the geosynthetic.