Bearing Capacity: Correlation between Soil and Rock Correction Factors

Abstract

n the field of soil mechanics, the calculation of the bearing capacity is well developed, there are various correction coefficients published by different authors that are used to take into account diverse hypothesis regarding self-weight, foundation type, foundation roughness, etc. However, in rock mechanics the application of these correction coefficients developed in soil mechanics can lead to erroneous results, so it is still necessary to carry out more research in order to know further the influence of multiple parameters of the rock mass on the bearing capacity of shallow foundation to estimate it with more accuracy applying different correction factors. Based on the limitations of different analytical solutions for the estimation of the bearing capacity of shallow foundation on rock mass, the numerical modeling of the shallow foundation by finite difference code FLAC is performed over a great number of cases. The purpose of that numerical modelling is to study the influence of geometrical and geotechnical parameters (foundation width, rock type, uniaxial compressive strength and geological strength index) on the bearing capacity of foundations on rock mass under different hypotheses of the self-weight of material, the footing shape and the roughness of the base interface. In this paper a summary of a comparison between the influence of different correlation coefficients in soils and rocks is presented in order to determine which parameter is more conditioning in each type of material and the mechanical behavior observed, analyzing quantitatively those differences as well.