Alternative for Lightweight Aggregate
Project: Citi Field
Owner: City of New York
Installed: 17,500 Cubic Yards
In July 2006, initial construction of the new Mets Stadium was underway in the parking lot beyond the old stadium’s left-field. The design called for the playing field to be elevated five to six feet above the grade of the old parking lot. However, the additional fill required to accommodate the design would add an estimated 700 pounds per square foot which was problematic because the extra weight would cause substantial settlement of the weak native soils in the area and require a lengthy surcharge of soils until the settlement subsided.
Most proposed solutions to this situation were cost and time prohibitive. The initial plan called for reducing the load on the underlying soils by using Lightweight Aggregate as fill. This would have yielded a density of ~55 PCF after compaction and the ability to hold 50% or more of its volume in temporary storm retention. However, when the owners learned that MixOnSite was installing foam concrete on a cross-town rival's new stadium, they decided to investigate further.
After further review, the decision was made to use a pervious foam concrete averaging 29 PCF and 80 PSI. This decision resulted in a direct savings of more than $500,000.00 along with an immeasurable savings of time. The only condition was that the foam concrete be as free draining as lightweight aggregate since the infield lacked the drainage system needed to accommodate a non-pervious material. This challenge was easily met using MixOnSite's Geofill LD Pervious material. The ultimate storm retention of the the material was approximately 70%.
More than 1,000 cubic yards was produced per shift using MixOnSite's high capacity dry mix equipment which allowed us to complete our scope of work well ahead of schedule.