BS 6089:2010

Foreword
Introduction
1 Scope
2 Normative references
3 Terms and definitions, symbols and subscripts
4 Relationship between standard specimen 28-day strength
  and in-situ strength
5 Planning an investigation
6 Additional procedures
7 Assessment where the strength of concrete based on test
  specimens is in doubt
8 Assessment where the producer has declared the concrete
  as nonconforming with respect to compressive strength
Annexes
Annex A (normative) - Guidance on the estimation of
        potential strength
Bibliography

Provides methods for determining the characteristic in-situ compressive strength in concrete structures and precast concrete components based on: - core testing; and - rebound hammer, ultrasonic pulse velocity and pull-out force measurements after a relationship with core strength has been determined for the particular concrete under investigation.

This British Standard complements BSEN13791, which gives methods for determining the characteristic in-situ compressive strength in concrete structures and precast concrete components based on: core testing; rebound hammer, ultrasonic pulse velocity and pull-out force measurements after a relationship with core strength has been determined for the particular concrete under investigation. This British Standard provides additional guidance on: planning an investigation (see Clause5); selection of test methods (see 5.4); selection of the test locations (see 5.5 and 5.6); assessment of individual core results within a group (see 6.1); assessment where the strength of concrete based on test specimens is in doubt (see Clause7). In addition, this British Standard provides guidance on the following cases not covered by BSEN13791: assessment of an unknown structure using a margin based on the t-statistic (see 6.2); use of indirect methods without correlation to core strength (see 6.3); relative testing, i.e. comparison of a volume of concrete under investigation with concrete in similar elements that has been accepted (see 6.4); action when the producer has declared nonconformity (see Clause8). This British Standard does not provide guidance on: the use of cores with a diameter of less than 50mm or the use of microcores; whether a structure has adequate durability; the use of in-situ testing as an alternative to conformity testing based on test specimens. NOTE For completeness, Figure1 and Figure2 identify such a procedure but this British Standard does not attempt to provide any of the necessary detail.