Tony
Alligator Snapping Turtle/Past Pres
From the auction thread:
These are pictures I took last week at the new National Fire Lab on the NIST campus in Gaithersburg. It was about an 800 cubic yard pour on an 4 foot thick elevated deck (!). The pour started at 4:00 AM and we were poured out around 9:00 or so. We used two 42 meter concrete pumps which were fed almost continuously by two ready-mix trucks at a time.
The grid on top of the slab was to hold the 1200 galvanized sleeves in place. The tolerance for placement of the sleeves is under 1/32" in any direction (X/Y/Z). Each sleeve weighs approximately 90 pounds. This is in addition to the 1900 tons of wet concrete and 160 tons of rebar (again - all in an elevated deck 10 feet off the 3' thick foundation mat).
Beyond the reinforcing steel, running through the middle of the slab are 27 runs of bonded 6-strand post-tension cable (approximately 2,100 LF of tendon or about 2.5 miles of individual strand). After placement and curing of the concrete, the tendons are individually stressed with a hydraulic ram to carry 257,000 pounds of tension each.
Tis glorious, no?
I love my job. It's like playing with giant Legos.
Not the biggest pour I've ever done on one of my jobs, but certainly the most complex.
These are pictures I took last week at the new National Fire Lab on the NIST campus in Gaithersburg. It was about an 800 cubic yard pour on an 4 foot thick elevated deck (!). The pour started at 4:00 AM and we were poured out around 9:00 or so. We used two 42 meter concrete pumps which were fed almost continuously by two ready-mix trucks at a time.
The grid on top of the slab was to hold the 1200 galvanized sleeves in place. The tolerance for placement of the sleeves is under 1/32" in any direction (X/Y/Z). Each sleeve weighs approximately 90 pounds. This is in addition to the 1900 tons of wet concrete and 160 tons of rebar (again - all in an elevated deck 10 feet off the 3' thick foundation mat).
Beyond the reinforcing steel, running through the middle of the slab are 27 runs of bonded 6-strand post-tension cable (approximately 2,100 LF of tendon or about 2.5 miles of individual strand). After placement and curing of the concrete, the tendons are individually stressed with a hydraulic ram to carry 257,000 pounds of tension each.
Tis glorious, no?
I love my job. It's like playing with giant Legos.
Not the biggest pour I've ever done on one of my jobs, but certainly the most complex.
