Chapter 4: Testing plan for the structural adequacy assessment of existing concrete structures

In addition to visual inspection of the existing concrete structure, a testing plan must be developed to obtain the information required for the assessment of structural adequacy of the existing concrete structure. Various tests for in situ strength of concrete and steel reinforcement of the existing concrete structure will be discussed. Sound engineering judgement and appreciation of factors influencing the various tests are required in developing the testing plan for estimating in situ compressive concrete strength of the existing concrete structure. There are precautions and practical considerations that must be recognised. These issues in using such tests to estimate in situ compressive strength will be discussed. An illustrative example to demonstrate the practical limitations of the different approaches of BS 6089 (BSI, 1981) and BS 6089 (BSI, 2010) to determine the in situ concrete strength is presented.