Consulting Civil Engineers
12000 Old Virginia Road
Reno, Nevada 89521
PH (775) 853-9100
Meadowood Mall Pile Driving
In the beginning of March 2016, we observed pile driving for seismic foundations for a new Dick’s Store at Meadowood Mall. This was a project that Jonathan had brought along from his previous employer – to finish the foundation recommendations and consult on the pile driving operations.
The foundation soils under the site included intermittent areas of liquefiable sands, at about 20 to 27 feet below ground surface – possibly a buried stream channel – generally surrounded by less liquefiable clayier or denser soils. At the south corner of the proposed new store, liquefaction settlement were predicted in the range of 3 inches. There was less than 1 inch of liquefaction settlement predicted at most other locations. To accommodate this geological problem, rather than require mitigation of the entire store foundation, piles were put under the walls and columns in the south corner, for a total of 17 piles. Tie beams are planned between the pile supported column locations. The rest of the store is supported on conventional spread footings with minimal foundation ties except the normal strip foundation under the perimeter wall.
Piles were 12-inch-diameter pipe piles driven with a Delmag D30-32 hammer. The structural had requested conical tips, although we were comfortable with a flat plate plug – one was installed with the flat plate because they had brought one tip too few. Piles were predrilled about 8 feet to ensure initial alignment. Piles were designed to develop capacity between 37 and 45 feet depth, and in fact we did achieve the design capacity at 41 to 44 feet depth.