Figure 3-18: Flowchart.

Flowchart for assessing the condition of the concrete paste as applied to the Spearfish, South Dakota site. This flowchart from Volume 2 of the guidelines shows how to examine the paste and air void system to determine if further evaluation of the aggregates is required. For the Spearfish, South Dakota site, examination of the paste and air void system showed the following conditions to be present and led to further examination of the aggregate:

• Cracks in the paste were present;
• No rust stains were found around embedded items;
• Freeze-thaw can occur;
• The original un-filled air void system is adequate;
• The air void spacing factor was not greater than 0.20 millimeters due to infilling;
• The air void system in the concrete near the road surface was not judged to be poor;
• Cracks extended through the aggregates into the paste suggesting a possible aggregate freeze-thaw may have occurred;
• Cracks or voids were filled, which led to the need to identify the in-filling materials;
• No softening or degradation of the paste; and
• No gaps around the aggregate were present.
  
  

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