Figure 3-60: Flowchart.

Flowchart for assessing the condition of the concrete paste as applied to NC-440-015. 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 Raleigh, North Carolina site, examination of the paste and air void system showed the following conditions to be present, which led to the 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 greater than 0.20 millimeters due to infilling suggesting that a possible paste freeze-thaw occurred;
• 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 that a possible aggregate freeze-thaw occurred;
• Cracks or voids were filled, which led to the need to identify the in-filling material;
• No paste softening or degradation; and
• No gaps around the aggregates.
  
  

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