Testing of concrete in structures

Abstract

According to the authors, “the principal aim of this book is to provide an overview of the subject for nonspecialist engineers who are responsible for the planning of test programs (p. III)” of hardened concrete in structures. The first edition of this book was published in 1982 and the second edition was published in 1989. Many developments have occurred since 1982, particularly in the field of in situ nondestructive testing. S.G. Millard joined Professor J.H. Bungey of the Department of Civil Engineering, University of Liverpool, in updating this third edition, which includes the description of many new developments and references. These are the contents: 1. Planning and interpretation of in situ testing (32 pages). This chapter is well documented. It describes the typical stages of the test program, presents in detail in situ concrete variability, and explains how to apply these results to specification and design calculations. Relevant British and American standards are listed, but it is essentially the British Standards that are considered in the remaining chapters. 2. Surface hardness methods (13 pages). This chapter concerns only the rebound principle; there is no mention of indentation testing, and penetration is discussed in Chapter 4. 3. Ultrasonic pulse velocity methods (35 pages). These methods are described in detail and the authors demonstrate a familiarity with techniques that are commonly applied in Canada. 4. Partially destructive strength tests (26 pages). This chapter deals with penetration resistance testing (Windsor probe and pin penetration), pull-out testing, pull-off testing, and break-off testing. Each test is well described and well illustrated. 5. Cores (18 pages). Here the authors discuss coring techniques, preparation of samples, and interpretation of the results, taking into account particularly the influence of the specimen’s size and elongation. 6. Load testing and monitoring (31 pages). In situ load testing is well illustrated as are the objectives of monitoring. However, the authors’ treatment of monitoring is somewhat superficial and unevenly balanced. Mechanical gauges are considered by them most suitable, which is no longer true since the development of automated data acquisition systems. Vibrating wire gauges are often preferred today. Apart from the consideration of optical fibre sensors, it would be pertinent to update this section of the book. 7. Durability tests (37 pages). These tests deal essentially with steel corrosion, moisture measurement, adsorption, and permeability tests. These tests are particularly detailed; however, the durability characterization requires a larger family of tests that are only superficially covered here and in Chapter 9. 8. Performance and integrity tests (31 pages). Important new techniques have developed in the past decade. Some of these new techniques presented here include radar, infrared thermography, x-ray, and gamma radiography. However, there is no mention of sonic or acoustic tomography techniques, although they are frequently applied to the evaluation of aged concrete dams. 9. Chemical testing and allied techniques (29 pages). These tests are related to the evaluation of the components of concrete (initial mix and environmental modifications) and specialized instrumental methods. Typical cases are presented in the appendix. The book includes over 300 references pertinent to each chapter. In conclusion, this book meets its objective of overviewing concrete testing in structures, and should be mandatory reading for every engineer planning in situ testing. However, it should be considered an introduction to be followed by more specialized books appropriate to one’s needs, particularly when monitoring structures and using tomographic techniques (integrity tests).