Paper contribution

Safe Footing Distance for an Isolated Footing Adjacent to an Excavation Wall in Jointed Rock Masses

Argha Biswas; Mahendra Singh; Aditya Singh

Proceedings
EUROCK 2026
Pages
581-586
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

Increasing land-use pressure often requires engineers to construct structures in close proximity to a vertical cut and supported by a retaining wall, particularly in hilly regions. In such cases, the footing’s distance from the vertical cut or excavation becomes a critical parameter, as it governs the extent to which excavation-induced effects can be minimized or neglected. Although footings may be placed on either soil or rock, identifying a safe footing location on rock is considerably more complex due to the anisotropic behavior of jointed rock masses compared with the relatively isotropic nature of soils. To investigate this, 2D physical model tests were conducted on an artificial 60°–30° orthogonally jointed rock mass with an isolated footing placed adjacent to an excavation wall. The experimental results indicate that when the footing is positioned beyond a certain safe footing distance, the excavation no longer affects the bearing capacity, regardless of the excavation depth. Complementary finite element modeling analysis was conducted to assess the bending-moment distribution, shear-stress distribution, and load transfer along the excavation wall. The numerical results likewise demonstrate that beyond the safe footing distance, bending moments, shear stresses, and applied loads exhibit similar patterns for different excavation depths.

Contributors

Authors

  1. Argha Biswas Indian Institute Of Technology Roorkee, India ORCID 0009-0008-1375-5679
  2. Mahendra Singh Indian Institute Of Technology Roorkee, India ORCID 0000-0003-3775-7026
  3. Aditya Singh Indian Institute Of Technology Roorkee, India ORCID 0000-0003-4749-2471

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References

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