Edged Inverted Folded Plate Shell Strip Foundation Bearing Capacity Comparison with strip footing on Sandy Soil

Document Type : Regular Paper


1 Ph.D. Candidate, Civil Engineering Department, Ferdowsi University of Mashhad, Mashhad, Iran

2 Associate Professor, Civil Engineering Department, Ferdowsi University of Mashhad, Mashhad, Iran


Using shell foundations as well as their benefits in the case of improved bearing capacity is investigated these days, especially strip folded shape. Because of more contact in soil, these type of shells have more bearing capacity than shallow foundations. In this research the behaviour of Strip Inverted Folded Plate Shell Foundation is studied on sandy soil. The elastic perfectly plastic numerical analyses and experimental tests are analysed and compared with shallow foundation. The effect of adding edge, variation in width and shell angle are considered. More than 45 geometrical shells models have been selected for research and the results are compared with common strip foundation in same width. Digital stress transducers are used for integrity of stresses and numerical model verification. The results indicate that adding edge with the same width and decreasing the B/D ratio in shell strip foundation improves the bearing capacity. Also when an edge on the toe of the foundation equivalent to the embedment depth is used the bearing capacity is improved in the range of 3-50%. Variation in shell angle with the same width results in increasing the bearing capacity up to two times. Finally, it is recommended to use a shell strip foundation with of 45º to 60º and with an edge equal to embedment depth.


Main Subjects

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  • Receive Date: 02 April 2021
  • Revise Date: 05 November 2021
  • Accept Date: 08 November 2021
  • First Publish Date: 08 November 2021