In late October 2019, a large sinkhole collapsed on 10th Street in Pittsburgh between Penn Avenue and Liberty Avenue. Following initial cleanup efforts, the City closed the street and adjacent sidewalk to vehicle and pedestrian traffic. The sinkhole damaged much of the underlying infrastructure. In May 2020, construction crews from Independent Enterprises, Inc. mobilized to begin the repair. Some of the work to be completed included repairing damaged telecommunications conduit, backfilling the sinkhole with 2A stone aggregate, installing granite curbs, rebuilding catch basins, reconstructing damaged sidewalks, stamping new concrete crosswalks, and installing tree boxes.
Independent Enterprises, Inc. contracted DLZ as a third-party material testing and certification group. DLZ worked with construction inspection personnel on-site while performing testing and material verification for the reconstruction of the area. DLZ completed compaction testing using a nuclear densometer on the compacted 2A Subgrade material, as well as field testing of installed concrete, and compressive strength testing of representative samples of the placed concrete for the reconstruction.