Effect of Facing Stiffness on Performance of Geosynthetic-Reinforced Retaining Walls Subjected to Footing Loading

Geosynthetic-reinforced retaining (GRR) walls have been used as bridge abutments to support shallow foundations. This technology eliminates the need for traditional deep foundations, such as piles, to support bridges. However, limited studies have been conducted so far to evaluate the performance of GRR abutment walls constructed with flexible wrapped-around facing. In this study, reduced-scale GRR abutment walls with wrapped-around and modular concrete block facing subjected to static footing loading were constructed in a test box under a plane strain condition in the geotechnical testing laboratory at the University of Kansas. Each model test wall had a dimension of 1.2 m long, 0.45 m wide, and 1.0 m high. Geogrid layers used as reinforcement in the walls had vertical spacing of 0.2H (H is the wall height) and length of 0.7H. The footing was 0.2 m wide and placed on the top of each wall with an offset distance of 0.2 m from the wall facing. The settlements of the footing, the lateral displacements of the facing, the vertical and lateral earth pressure, and the failure mode were evaluated in this study. The experimental results showed that the modular block facing acted as a relatively rigid structural element that reduced the footing settlement as compared with the wrapped-around facing. Moreover, the maximum lateral displacement in the wrapped-around facing wall was about much larger than that of the modular block facing wall under the same applied footing pressure. The 2:1 distribution method reasonably calculated the vertical stress at the base of the wall at the centerline of the footing. The maximum lateral earth pressure was recorded at the depth of 0.3H and 0.5H from the top of the walls with modular block and wrapped facing, respectively. The FHWA and AASHTO method calculated the lateral earth pressure induced by footing loading approximately matching that measured for the wall with modular block facing, but quite different from that for the wall with wrapped-around facing. Shallow, middle, and deep slip surfaces were observed in these test models while they were at failure.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AFS10 Standing Committee on Transportation Earthworks.
• Authors:
  • Rahmaninezhad, Seyed Mustapha
  • Han, Jie
  • Kakrasul, Jamal I
• Conference:
  • Transportation Research Board 97th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2018-1-7 to 2018-1-11
• Date: 2018

Language

• English

Media Info

• Media Type: Digital/other
• Features: References;
• Pagination: 5p

Subject/Index Terms

• TRT Terms: Bridge abutments; Earth pressure; Facings; Footings; Geosynthetics; Loads; Performance tests; Retaining walls; Stiffness
• Subject Areas: Bridges and other structures; Geotechnology; Highways; Materials;

Filing Info

• Accession Number: 01657902
• Record Type: Publication
• Report/Paper Numbers: 18-04884
• Files: TRIS, TRB, ATRI
• Created Date: Jan 25 2018 9:33AM