DESCRIPTION

This multi-sport and entertainment venue was designed to operate year-round to host training programs, games, and tournaments for soccer, football, lacrosse, rugby, and softball. Stadium users include youth, high school, college, adult, and professional athletes. Concerts, cultural fairs, and charitable events are also held at Highmark Stadium. The Stadium serves primarily as the home field for the Riverhounds soccer team. The new stadium seats approximately 3,500 individuals on the south and east sides of the field for the Riverhounds home games and other sporting events. The north side of the field remains opened to provide visitors with views of the Pittsburgh skyline.

CHALLENGE

The project site consist of layers of deep fills, alluvial silts, clays, sand and gravel underlain by claystone bedrock. Highly fluctuating water tables are present at the project site due to the proximity of the adjacent river.

SOLUTION

Based upon GeoStructures review of subsurface conditions and proposed plans, The Impact® system was selected to provide economical foundation support and settlement control proposed for shallow foundations. Displacement Impact elements were installed without augering or casing using a filled open pipe. Once at design depth, the mandrel pipe was filled with stone and raised 3 to 4 ft. Using vibration and downward hydraulic force, the open-graded stone is compacted using a beveled mandrel head to a height of 1 ft resulting in a 15 to 20-inch diameter Impact element.