grizbeer wrote:The field looked pretty good, it seems it is possible to keep a grass field in good condition even if it freezes and snows.
Nothing amazing about why Philly stadium was so playable last night. It just takes a little money.
The Lincoln Financial Field has a turf-warming system. The playing surface is constructed with a top canopy of the turf, then 10 in. of root zone, a sand layer, a peat layer, diatomaceous (silica-based) earth mix designed to hold moisture and then below that is the PEX tubing (Turf-Warming system). Below that is 12 in. to 18 in. of pea gravel for drainage and the tubing for the pop-up irrigation system.
The field is broken into six zones, covered by nearly 40 miles of 34-in. ZurnPEX tubing spaced 9 in on center. Each circuit is about 400 ft.
Two circulator pumps feed the circuits, each moving 300 gpm at 100 ft. of head. The circuits contain ball valves for isolation and zone valves in the boiler room for control. The system is piped reverse return.
The field system is DDC controlled via laptops that fire the boilers in sequence and control the zone pumps. There are eight field sensors in each zone, placed high strata and low strata and in four different locations. The sensors then average the temperatures and tell what zones to start up. The engineers did a shade study on what parts of field will have sun at what times.
With all this, I still like the idea of covering it with a tarp and using tarp cleats as mentioned.
Save the earth. It's the only planet with chocolate.