Geomechanics and Engineering

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The behaviour of a strip footing resting on geosynthetics-reinforced slopes

  • Hamed Yazdani (Faculty of Civil Engineering, Babol Noshirvani University of Technology) ;
  • Mehdi Ashtiani (Faculty of Civil Engineering, Babol Noshirvani University of Technology)
  • Received : 2023.03.03
  • Accepted : 2023.08.11
  • Published : 2023.09.25
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Abstract

This study utilized small-scale physical model tests to investigate the impact of different types of geosynthetics, including geocell, planar geotextile, and wraparound geotextile, on the behaviour of strip footings placed on 0.8 m thick soil fills and backfills with a slope angle of 70°. Bearing capacity and settlement of the footing and failure mechanisms are discussed and evaluated. The results revealed that the bearing capacity of footings situated on both unreinforced and reinforced slopes increased with a greater embedment depth of the footing. For settlement ratios below 4%, the geocell reinforcement exhibited significantly higher stiffness, carrying greater loads and experiencing less settlement compared to the planar and wraparound geotextile reinforcements. However, the performance of geocell reinforcement was influenced by the number and length of the geocell layers. Increasing the geocell back length ratio from 0.44 to 0.84 significantly improved the bearing capacity of the footing located at the crest of the reinforced slope. Adequate reinforcement length, particularly for geocell, enhanced the bearing pressure of the footing and increased the stiffness of the slope, resulting in reduced deflections. Increasing the length of reinforcement also led to improved performance of the footing located on wraparound geotextile reinforced slopes. In all reinforcement cases, reducing the vertical spacing between reinforcement layers from 100 mm to 75 mm allowed the slope to withstand much greater loads.

Keywords

Acknowledgement

The authors would like to acknowledge the financial support provided by Babol Noshirvani University of Technology under grant No. BNUT/395032/00.

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