ABSTRACT
Concrete specifications can play an important role in ensuring good quality concrete. This chapter makes suggestions on concrete specifications with the aim of improving concrete quality.
Almost all concrete project specifications have a specified compressive strength, f ′c, requirement for concrete mixtures. Mixtures are designed to meet the required average compressive strength, f ′cr, to ensure that the strength tests meet the strength acceptance criteria. ACI 318 and 301 provide two options to establish the required average strength f ′cr. These options are provided in Appendix A. The first option, referred in this chapter as Option A, makes use of the standard deviation, S, established from past strength test records, while the second option, referred in this chapter as Option B, adds a fixed strength increase when no past test records are available.
