Characterization of Frictional Interference in Closely-Spaced Reinforcements in MSE Walls

015414562014Final ReportPDFTech Report2012-S-OSU-0009DTRT12-UTC10Earth wallsFrictionStrain (Mechanics)Reinforced earthBackfill soilsPull out testStressesResearch HubBridges and other structuresGeotechnologyHighwaysI24: Design of Bridges and Retaining WallsI42: Soil MechanicsUnited StatesPacific StatesPacific Northwest Transportation ConsortiumStuedlein, Armin W.Walters, James J.Strahler, Andrew W.Oregon State UniversityUnited States. Dept. of Transportation. Research and Innovative Technology AdministrationUS Transportation CollectionThis research addresses one of several knowledge gaps in the understanding of tall Mechanically Stabilized Earth (MSE) wall behavior: prediction of reinforcement loads impacted by frictional interference of closely-spaced reinforcements associated with tall walls. Key findings of this research include: (1) New backfill-specific and gravelly-soil models for the prediction of the apparent friction coefficient with normal effective stress were developed for use with ribbed steel strip reinforcements. (2) The performance of the proposed pullout resistance design models were compared to the current American Association of State Highway and Transportation Officials (AASHTO) design model and found to produce significantly more accurate predictions of the apparent friction coefficient. (3) Preliminary test results indicate that frictional interference appear to exist in the vertical direction at vertical pressures of 100 kPa and may increase the peak pullout loads of reinforcement strips as much as 40% at a spacing of 152 mm