Retaining Walls for a Sunken MLS Stadium-PPT Presentation

PPT Presentation

Pdf Summary

The presentation describes the design and construction of retaining walls for a new MLS stadium in downtown Columbus, Ohio. The stadium occupies part of a 21-acre brownfield development near the confluence of the Olentangy and Scioto rivers, within the 100-year floodplain. The concourse is at elevation 727 feet, the field at 705 feet, and groundwater can reach approximately 722 feet.<br /><br />The subsurface profile consists of clay fill and clay to about 20 feet, alluvium to 35 feet, glacial till to 75 feet, and shale and limestone below. The primary retaining system is a secant pile wall: 653 primary and secondary piles, each 46.5 inches in diameter, totaling about 2,300 linear feet. The piles extend to rock. The wall was designed for temporary cantilever excavation conditions and permanent conditions, when it is braced at a grade beam.<br /><br />Separate retaining walls support the pitch access tunnel. These use 45 soldier piles, 36 inches in diameter and extended to rock; 33 are anchored and 12 are cantilevered. The 33 strand anchors are designed for loads of 160–220 kips, with lengths of 49–58 feet and downward angles of 40–45 degrees. Tunnel-wall design involved staged analysis to evaluate earth pressures, anchor loads, and bending moments.<br /><br />Construction activities included installing guide walls, primary and secondary secant piles, excavation behind the secant wall, and staged installation of the tunnel walls and anchors.

Keywords

retaining walls

MLS stadium

Columbus Ohio

secant pile wall

brownfield development

floodplain

soldier piles

strand anchors

pitch access tunnel

excavation support