3D Finite Element Analysis of the Geosynthetic Reinforced Soil-Integrated Bridge System (GRS-IBS) Under Different Loading Conditions

In this study, a three-dimensional (3D) Finite Element (FE) analysis was developed to simulate the fully-instrumented geosynthetic reinforced soil integrated bridge system (GRS-IBS) at Maree Michel Bridge in Louisiana. The 3DFE computer program PLAXIS 3D 2016 was selected to simulate the GRS-IBS behavior under different loading conditions. A second order-hyperbolic elasto-plastic soil model was used to simulate the granular backfill materials. The soil-structure interaction was simulated using zero thickness interface elements, in which the interface shear strength is governed by Mohr-Coulomb failure criterion. Three different loading conditions were considered in this study: (a) at the end of bridge construction (Case 1); (b) surface loading (Case 2); and (c) at abnormal loading (Case 3), which is equal to the dead load of the bridge structure plus three times the service loading. The predicted results were compared with the field measurements at the end of bridge construction. Moreover; the predicted results of the 3D-FE analysis were compared with those predicted using the 2D-FE analysis. A good agreement was obtained between the 3D-FE and 2D-FE numerical results and the field measurements. The predicted results using the 3D-FE showed that the range of maximum reinforcement strain under service loading ranges between 0.6% and 1.5%, depending on the location of the reinforcement layer. The maximum lateral deformation at the face was between 3 mm (0.07% lateral strain) under service load case and 7 mm (0.3% lateral strain) for abnormal load case. The maximum settlement of the GRS-IBS due to the service loading was 9 mm (0.3% vertical strain). The axial reinforcement forces predicted by FHWA (Adam et al.2011) design methods were compared with those predicted by the 3D-FE and 2D-FE analysis. The results showed that the FHWA analytical method is 1.5–2.5 times higher than those predicted by the FE analysis, depending on the loading condition and reinforcement location.

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  • English

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  • Accession Number: 01672003
  • Record Type: Publication
  • Files: TRIS
  • Created Date: May 18 2018 4:18PM