Constitutive laws for geomaterials

Abstract

An abundance of constitutive laws exists to approximate the behavior of geomaterials under various stresses, boundary conditions and loading paths, pore pressures, temperatures and so on. The construction of constitutive laws is driven by two competing trends: the tendency for a unifying law describing the material behavior under the most general conditions, and the need for laws that can be used efficiently in practice. The latter incorporates both the possibility of calibration from available specimens and the user-friendliness of the law. For engineering purposes, the second tendency dominates and the engineer scientist has to evaluate the problem and select the most appropriate model to describe the dominant phenomena on hand. A review of various constitutive laws for geomaterials is presented with an emphasis on their application. Various examples of engineering problems and geomaterials with emphasis on petroleum applications are used to demonstrate that the law must be as simple as possible but not simpler. Copyright © 1999, Editions Technip.