A Cavity Expansion Model and Its Interpretation towards Field Testing of Inclined Penetrations

摘要

It is expected that the measurements of tip resistance will be different between vertical cone penetration tests and inclined cone penetration tests. In this paper, a cavity expansion model was first proposed to theoretically compare the different measurements at different penetration orientations based on initial stress anisotropy. Then a field testing program was performed in three different locations with varying soil characteristics in Louisiana. It was found that, the coefficient of lateral earth pressure at rest, K_o, which indicates the degree of initial stress anisotropy, governs the relative magnitude of tip resistance measurements at different penetration directions. The tip resistance tends to increase for K_o < 1 or decrease for K_o > 1 as the orientation of penetration changes gradually from vertical to horizontal.