The design of shallow foundations on fractured rock

Authors

  • Néstor R. Espinoza Universidad de Valparaíso, Valparaíso, Chile image/svg+xml
  • Jorge A. Arriagada Universidad de Valparaíso, Valparaíso, Chile image/svg+xml
  • Lorna González Universidad de Valparaíso, Escuela de Ingeniería Civil, Valparaíso, Chile; NREG Consultores en Geotecnia, Chile
  • Nazer Nazer Universidad de Valparaíso, Escuela de Ingeniería Civil, Valparaíso, Chile; Laboratory Manager, IDEAS, Institute of Testing, Analysis and Drilling, Chile

DOI:

https://doi.org/10.21703/0718-2813.2025.37.3242

Keywords:

Shallow foundations, Bearing capacity, Rock mechanics, Finite element method

Abstract

Designing shallow foundations on fractured rock is a complex challenge for civil engineers due to varied geological structures and material properties. Unlike soils, estimating rock mass bearing capacity using soil mechanics methods is often unsuitable due to irregular block dimensions. Factors like discontinuities, filling materials, and fracture intensity further complicate developing a universal theory akin to Terzaghi’s for soils. Peck introduced a method correlating bearing capacity with Rock Quality Designation (RQD), followed by approaches based on Bieniawski’s Geomechanics Classification System and empirical methods. Despite advancements in numerical modelling, no universal solutions exist. This study analyzes fractured rock behaviour using Chilean site samples, employing finite element models to compute shear stresses and deformations. The goal is to propose a comparative method integrating empirical and numerical approaches, evaluating result dispersion.

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Published

2025-05-28

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Articles

How to Cite

The design of shallow foundations on fractured rock. (2025). Obras Y Proyectos, 37, 106-114. https://doi.org/10.21703/0718-2813.2025.37.3242