Observations/Finding

At the request of the client’s representative, our AS ENGINEERING AND CONSULTING, LLC (ASEC) representative, Amin Azimi, visited the job site to observe the contractor’s work activities from a quality assurance standpoint. The purpose of the visit was to verify compliance with project drawings, specifications, applicable codes, approved material submittals, and to conduct QC testing in accordance with project requirements.

Observations for This Shift:

• Compaction Testing:
  Compaction testing was performed on Section 1B between STA 1048+50 to 1080+00 on Runway 3R-21L using a Troxler nuclear density gauge, supplemented by general probing with a 3/8″ diameter probe rod. The density test results indicated that most of the compacted materials did not meet the project requirement of achieving a minimum of 100% of the maximum dry density, in accordance with ASTM D1557 (Modified Proctor).

• Performed demolition for taxiway between STA 79+00 to 86+00 on this day.

• Proof Rolling Observation and Performance:
  A proof roll was conducted on Section 1B between STA 1048+50 to 1080+00 on Runway 3R-21L using a fully loaded tandem axle truck. Multiple passes were made across the subgrade. During the proof roll, some yielding and deflection were observed throughout the tested areas, indicating insufficient subgrade stability.

• NOTE: From STA 1052+00 to 1057+75 subgrade yielding and deflection were not observed.
• The second crew was mixing lime with the soil and compacting it for station 1A.
• Two (2) buckets of GAB were transferred to the lab to perform a moisture-density relationship.

• Recommended Corrective Action:
  Due to high moisture content and low compaction results, it was recommended that the soil be treated with lime and recompacted to improve stability and meet project requirements.

• Additional Personnel Present:
  The proof-roll was jointly performed and observed by the undersigned (Amin Azimi), Andres Nova (QA Representative), and Tony (CWM Representative).

We appreciate the opportunity to be of service on this project. Should you have any questions regarding this report, please do not hesitate to contact us. We would be pleased to discuss our findings further.