Analysis of beams on reinforced granular beds

摘要

This paper presents a model for estimating the flexural response of beams resting onnreinforced beds with reinforcing elements, such as geogrids, which are idealised as beams withnsmooth surface characteristics. The lower poor strata and the upper dense soil are modelled usingnWinkler springs of different stiffnesses. Taking a surcharge load on the reinforcing elements hasnincorporated the effect of depth of placement of the reinforced layer. The governing differentialnequations to find the response of the model have been derived, and closed-form analytical solutionsnare found subjected to appropriate boundary and continuity conditions. A particular case of thenpresent study matches identically when compared with the solution obtained by Hetenyi for anninfinite beam on an elastic foundation. For the range of parameters considered, the results show thatnpractically no change occurs in the normalised deflection of upper and lower beams when thennormalised length ratio of beams exceeds 1.5. Further, it is shown that the various parameters—thenratio of flexural rigidity of upper and lower beam, the ratio of stiffness of the upper and lower soilnlayers, and the ratio of the length of upper and lower beams and placement depth of the lowernreinforcement—significantly affect the combined response of the model.