Facilities

Test Floor

The main test floor of the Structures Laboratory is a heavily reinforced concrete slab providing 8400 sq ft (780 sq m) of useable test area. This area is serviced by two 25 ton (222 kN) overhead cranes with a clear height of approximately 32 ft (10 m). The laboratory floor measures 150 x 56 x 3 feet, length x width x thickness (45 x 17 x 0.91 m), and has about 2000 tie down holes on a 2 x 2 foot (0.61 x 0.61 m) grid (see Figure 1). The floor was designed as a one-way slab supported by two north-south basement walls, three intermediate bearing walls and a footing slab at grade.Principal reinforcement includes top and bottom mats of #14, grade 60 bars at 12 in (305 mm) centers in both directions.All slab-wall and wall-footing joints are monolithic. As a result, the test floor, basement walls, and footing slab form a box girder that is 15 ft (4.5 m) deep, 56 ft (17 m) wide and 101 ft (31 m) long. Specified concrete strengths were 4000 psi (28 MPa). Test cylinder strengths at 28 days reached 5000 psi (34 MPa).