Coarseness Factor Chart Excel Spreadsheet

The chart shows a number of zones which estimate the concrete mix’s properties.

• Zone 1 – This area shows that the mix is gap graded. These mixes will have a high potential for segregation during production or compaction and pavements constructed with these mixes are often susceptible to localized cracking, blistering, spalling and scaling defects. They can be identified in the field as they are not cohesive, there will be a clear separation between the mortar and the coarse particles.
• Zone 2 – This is the optimum range for concrete pavement mixes with nominal maximum aggregate sizes between 20mm and 50mm. Mixes in this range will typically produce consistent, workable and high quality concrete pavements.
• Zone 3 – This zone can be the optimal range for concrete mixes with nominal maximum aggregate sizes smaller than 20mm.
• Zone 4 – This zone indicates that the mix has excessive fines content. These mixes will produce concrete with variable strength, high shrinkage, curling and cracking and are susceptible to spalling and scaling defects. There will also be a high risk of segregation during concrete production and compaction.
• Zone 5 – This zone indicates that the mix has an excessive amount of coarse aggregates and will not be sufficiently workable.
• Trend Bar – This zone indicates that the mix includes a near perfect balance between crushed aggregates and natural sands which will allow the fine aggregates to fill the voids between the coarse aggregates. It is difficult to consistently produce aggregate mixes which sit in this zone.