UFC 3-270-03
15 March 2001
sand-cement mortar of one part cement to two parts sand. The water-to-cement ratio should not
exceed 0.40 by weight.
13.2. Alternative Repair Materials. Spall repair materials can be classified into three broad
categories: cementitious, polymeric, and bituminous. Only the cementitious or polymeric
materials are approved for use on airfields. Bituminous materials must not be employed as a
spall repair material on Army and Air Force airfields due to the potential for FOD. Typical
concerns for selection of a spall repair material are cost, physical properties, curing time (how
soon can the section be opened to traffic), material availability, familiarity with the product, etc.
There are numerous products for concrete repair that address various aspects of the repair
project such as high early-strengths, rapid set times, ease of workability, low shrinkage, and low
permeability. However, since use of rapid-setting concretes and polymer concretes may require
very different placement and curing procedures, personnel should be aware of what is required
for the repair material before making a decision. Use of admixtures in PCC, rapid-setting, and
polymer concretes must meet appropriate specifications (ASTM C 260 and C 494 (Table 1.1.). If
using fast-setting polymer concretes or admixtures, the manufacturer's recommendations on the
use and cleanup of these materials should be followed to avoid problems. Mixing procedures for
the polymer concretes vary depending on the material. Concrete mixes may harden much faster
when temperatures are above 90 degrees Fahrenheit (32 degrees Celsius). Retarding
compounds can be added to the mixtures to slow the curing process at pavement temperatures
above 90 degrees Fahrenheit (32 degrees Celsius), or special mixtures premixed with retarders
that extend the setup time are also available. Due to the high heat released upon curing of many
of the polymer materials, only 2-inches (50-millimeters) or smaller lifts are suggested. Cleanup of
rapid-setting materials must begin soon after placement to prevent these materials from ruining
equipment. Guidelines for use in placement of polymer concretes are provided in ACI 548.1R
(Table 1.2.).
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