Relationship between small and large strain solutions for general cavity expansion problems in elasto-plastic soils

This paper presents a closed-form relationship between small and finite strain cavity expansion solutions. Its derivation is based on the non-linearly elastic–perfectly plastic cylindrical (or spherical) problem considering a general Mohr’s criterion and constant plastic dilatancy. It is shown, however, that it is sufficiently accurate for general expansion problems not obeying plane-strain rotationally (or spherically) symmetric conditions and involving strain-hardening/softening constitutive behaviour. Therefore, this relationship quantifies the error stemming from the computational assumption of small deformations and provides a simple and efficient way of accounting for geometric non-linearity based entirely on conventional computational methods: ‘self-correction’ of small strain analyses results.