Review of scientific insights and a critical analysis of pile capacity and pile integrity tests

Abstract

Modern geotechnical engineering is based on a multidisciplinary approach to solving complex geotechnical problems through engineering-geological soil testing, laboratory analyses of physical and mechanical soil properties, developing constitutive models of soil behaviour, in-situ testing of geotechnical structures, experimental-laboratory testing of geotechnical structures and developing of analytical-numerical models for the analysis of geotechnical structures. In addition to structures formed only from the soil, geotechnical structures also include geotechnical injections, combination of soil and reinforced concrete (RC) elements, primary RC structures in the soil, structures from geotextiles/geogrids/geocells and the like. In the group of geotechnical structures, where the primary role is played by the RC structure in the soil, a specific place is taken by the issue of analyzing the capacity and integrity of piles. There are a large number of analytical and numerical methods developed for the purpose of determining the capacity and integrity of piles, as well as a large number of in-situ tests of real piles constructed in the ground. Also, a series of alternatives were developed for solving problems in the everyday engineering practice and scientific research. Despite of this, there are a number of unresolved issues in determining the capacity and integrity of piles, especially in case of piles in existing structures. This raises a number of questions, such as: what method, when and for what type of piles should be used? Answers to these questions can be found in a variety of publications, but there are a considerable number of questions to be answered in order to enhance the practice and scientific knowledge in terms of analyzing the capacity and integrity of piles, and develop new sophisticated and reliable solutions. This paper provides a summary of pile capacity and integrity tests for quick and reliable assessment and the choice of the type of test in different situations. The paper analyzes the most commonly used tests in practice, as well as tests of new generation which have been increasingly used and may replace some proven reliable tests.