Observations/Finding

As requested, the site was visited by our AS Engineering and Consulting (ASEC) representative for the purpose of providing quality control inspection and testing services.  Visual observation techniques were employed to verify compliance with project drawing/specifications, applicable codes, and materials submittals. The following observations were observed on site this day.

Following up on the progress from the previous day, work has continued behind Lots #224-#229. The contractor has made progress in the preparation of the retaining wall foundation.

Focusing on backfilling and compaction operations behind the newly installing retaining wall sections along Lots #224–#229. Following the drainage installation, the next layer of backfill was placed over the previously installed geogrid reinforcement sheet, in preparation for subsequent compaction.

Following modifications to the retaining wall design, the wall height was reduced and extended nearly to the top of the diamond grid. With these changes in place, the subsequent excavation and fill placement were carried out using a Kobelco 310LC excavator. The fill material was then transported and distributed uniformly across Lots #224–#229 by a Bobcat 265 compact track loaders. Once the fill was evenly spread, compaction was performed using a Bomag BW211 sheepsfoot roller.

Nuclear gauge density testing was conducted on the compacted layer near each individual lot and also near the retaining wall to evaluate moisture content and dry density. The results showed compaction levels exceeding 95% in some locations but falling short in others. Based on this data, the superintendent was advised to dedicate additional time to compaction in areas with insufficient density. After re-compaction, general probing and proof-rolling tests were performed.

Upon successful compaction of the lift, the contractor advanced to the next layer of backfill. This subsequent layer underwent the same testing and quality control process.  Near the wall the compaction is carried out with remote compactor BMP8500 for even compaction along the retaining wall.

We appreciate the opportunity to be of service to you on this project. If you have any questions regarding this report, please feel free to contact us. We will be more than happy to discuss it with you.