Incentive Specifications for Concrete


  • The International Concrete Abstracts Portal is an ACI led collaboration with leading technical organizations from within the international concrete industry and offers the most comprehensive collection of published concrete abstracts.

International Concrete Abstracts Portal


Title: Incentive Specifications for Concrete

Author(s): Edward A. Abdunnur

Publication: Concrete International

Volume: 4

Issue: 9

Appears on pages(s): 20-24

Keywords: accelerated tests; acceptability; com-pressive strength; concrete construction; contrac-tors; quality control; specifications; standard devia-tion; tests.

Date: 9/1/1982

The basic philosophy that a specification is a means of communication between the owner and the contractor, and at the same time is part of legal con-tractural documents, is outlined, and advantages are set forth. The effect of variability of specifications and how it can be used to produce incentives for the contractor to set up quality control are discussed. The application of these principles to concrete strength specifications is outlined in some detail. Four basic integral parts in a specification are defined, and the application of the incentive approach is shown. In Part A, the average strength required is indicated to be the required f, plus a factor that is shown to be a constant multiplied by the standard de-viation. The way of arriving at the starting level for the required average is outlined in Part B. In Part C, the need for sampling plans and test methods to be defined in the specification is outlined. In Part D, the evaluation of the average and adjustments of this average depending on the job standard deviation are detailed. The usefulness of accelerated testing and the difference in specification factors between structural concrete and pavement and mass concrete are given. Finally, comparisons between incentive and penalty specifications are shown. It is concluded that penalty specifications develop an adversary contractural relationship that leads to increased construction delays and acceptance of lower quality than specified. In contrast, incentive specifications foment a team effort and cooperative relationship between the contractor and owner, reduce costs and construction time, and attain the quality required.