Non-Destructive Evaluation of Deep Foundations

Abstract

Non-Destructive Testing (NDT) or Non-Destructive Evaluation (NDE) of a great variety of materials and structures has become an integral part of many manufacturing processes. The same tendency towards more testing for improved quality assurance is also apparent in the deep foundation industry. However, the process of testing long piles, deeply embedded in the ground, is more complex than the NDE of other materials: the product can only be accessed from its smallest side and the material is often concrete or timber, which are rather heterogeneous materials with unreliable properties. The greatest difficulties, however, are presented by the intimate contact between pile material and soil, causing dissipation of the NDT energies to varying degrees. Nevertheless, there has been progress made with improving these methods and they have been employed in a wide variety of scenarios. This paper summarizes the most common non-destructive test methods and gives a few examples of applications with an emphasis on a demonstration of their benefits and limitations.