This project was developed on a construction spoil fill site located along I-279 in the northern part of Pittsburgh, Pennsylvania. Ground improvement was needed to support a two story building and satellite dish farm totaling an area of about 40,000 square feet. Maximum column loads ranged from 40 to 200 kips. The building was constructed using a slab-on-grade and spread footings approach. The fill at the site originated from the construction of I-279, where excavated rock and soil were dumped in a valley located at the now current WPXI building location.
The initial design called the for the building to be placed on drilled shaft foundations. Removal and replacement of the fill was not practical due to the depth that the fill extended. A ground improvement approach of dynamic compaction (DC) was ultimately suggested by the owner’s engineer and was determined to be most economical.