MrBMarsh
Civil/Environmental
- Sep 20, 2016
- 1
I have recently received the modified proctor lab results for P-209 crushed aggregate base we plan on using as a base for a new taxiway. The sample was collected at the quarry and taken to a construction materials lab for testing. The lab result indicated an uncorrected maximum dry density of 148.5 pcf at an optimum water content of 4.1%. After correcting for the oversized fraction, the oversize corrected density was 151.6 pcf and the oversize corrected moisture was 5.2% (the percent retained on the 3/4" sieve was 28%). The problem - I expected to see a dry density around 148 pcf (4.0% moisture) which is where P-209 from this quarry typically falls. With the corrections added, there is NO WAY to get 100% compaction at that moisture per the specifications given. After approximating the zero air voids curve on the moisture-density curve, the uncorrected moisture-density curve looks good. However, when you apply the correction factor, it is way right of the zero air voids curve which, I assume with little knowledge of the subject, is not possible.
Could someone help me with this??? I am very concerned that something is not right and I do not know the right questions to ask. I have attached the results I received.
Could someone help me with this??? I am very concerned that something is not right and I do not know the right questions to ask. I have attached the results I received.