The shear strength behaviour of two peaty soils.

This paper presents experimental research concerning the shear behaviour of two type of Italian peats, one normally, the other over consolidated. Organic soils are characterized by very high compressibility and high fiber content; two features that give rise to several problems during laboratory tests. Under consideretions here are the effects of fiber and overconsolidation over friction angle and shear-strain behaviour. These are evaluated by means of undrained compression triaxial tests, with isotropic and anisotropic (Ko) consolidation being performed on natural and remolded samples. The experimental results are also analysed by means of a bilinear failure criterion based on soil-reinforcement interaction mechanisms