Response of beams on a tensionless extensible geosynthetic-reinforced earth bed subjected to moving loads

Abstract

In this paper analysis of an infinite beam resting on reinforced granular bed overlying a soft soil strata subjected to a moving load with constant velocity is presented. The separation between the beam and ground surface is taken into the account while analyzing the system. The upper reinforced granular bed is modeled by a rough membrane embedded in Pasternak shear layer overlying a series of compressible Winkler springs representing the underlying soft soil. The extensible geosynthetic is assumed to deform such that at interface the geosynthetic and the soil have same deformation. This condition eliminates the two interfacial shear stress parameters and at the same time also incorporates the stiffness of geosynthetic in the model. The lift up of the beam and mobilized tension in the geosynthetic layer are observed to be more for the tensionless foundation as compared to that reacting in tension and compression. It has been further observed that the flexural response of the infinite beam as well as of the reinforcement, are greatly affected by the velocity, intensity of load, relative compressibility of granular fill and stiffness of the geosynthetic. For the range of parameters studied the shear moduli of granular layers do not significantly affect the response of the beam.