Question

Stresses obtained from Boussinesq's theory are considered reasonably satisfactory in foundation engineering because

• A. they represent stress distribution in inhomogeneous soils below loaded area
• B. they account for anisotropy of soil property
• C. they give due regard to plastic behaviour of soils, particularly for settlement analysis
• D. they consider elastic soil medium, and the intensity of allowable stresses below foundations in most cases are quite small and justify elastic solutions

Answer 1

The correct option is D they consider elastic soil medium, and the intensity of allowable stresses below foundations in most cases are quite small and justify elastic solutions

Boussinesq's theory is based on the following assumptions :
(i) The soil medium is elastic, homoge-neous, isotropic and semi infinite medium.
(ii) The medium obeys Hooke's law.
(iii) The self weight of the soil is ignored.
(iv) The soil is initially unstressed.
(v) The change in volume of the soil upon application of the loads on to it is neglected i.e., it is non-dilatant.
(vi) The top surface of the soil medium is free from shear stresses and is subjected to only point loads.
(vii) The stresses are distributed symme-trically with respect to vertical axis.