Guide to Formed Concrete Surfaces
|Publication Date:||1 January 2013|
The scope of this guide is to solve a lack of uniformity in the appearance criteria of concrete surfaces, provide definitions for the various levels of formed concrete surfaces, and give objective evaluations of them. Although there are various reference sources for constructing and evaluating concrete surfaces, none exist that offer a comprehensive guidance and understanding to its production and evaluation. Several ACI and ASCC documents, however, do provide partial guidance:
1) ACI 347-04 provides terms for classes of formed concrete surfaces, discusses irregularities in formed surfaces, and gives general guidance for the use of formwork for concrete;
2) ACI 309R-05 provides terms about visible effects of consolidation on formed concrete surfaces, why they occur, and how to avoid them;
3) ACI 303R-12 discusses architectural concrete, applications, and details of production including formwork, release agents, repair, and economics;
4) ACI 301-10 specifies concrete surfaces (Section 188.8.131.52);
5) The ASCC Education and Training Committee (1999) guide uses samples of concrete surfaces to illustrate appearance expectations.
These references, which exclude uniform appearance criteria or a process for evaluating formed concrete surfaces, make it difficult to achieve a wide range of expectations. The ultimate authority on a project is the contract document. The contract document is a guide for the:
a) Designer to specify the desired surface finish;
b) Owner to understand what the final product will approximately look like;
c) Contractor to select facing materials, concrete mixture, release agents, and construction methods to achieve the specified surface finish.