Laserfiche WebLink
III. STRUCTURAL DESCRIPTION <br /> Overview <br /> With the exception of an L-shaped mezzanine at the southeast corner of the building, the structure <br /> is typically one-stdry with a partial basement. The typical framing of the roof and structured floors <br /> is structural steel with the exception of the atrium at the north end of the building. At the atrium, <br /> ■ both the roof and floor of this area are constructed with cast-in-place concrete. This narrative deals <br /> with the building as two separate areas. The first area is the atrium, and the second area is referred <br /> to as the Typical Structure. Existing structural drawings for the building have not been obtained at <br /> the time of this report, and so the description is based upon a site visit on December 12, 2000 and <br /> experience with similar structures. <br /> Atrium <br /> r The atrium is located at the north central part of the building. <br /> Roof <br /> The roof is a hyperbolic shell constructed of cast-in-place concrete. 10 concrete columns spaced at <br /> about 67' support the roof, which is <br /> approximately 400' by 200' in plan. The <br /> shell is formed with concrete beams, <br /> which cantilever in four orthogonal <br /> ■ directions from each column. A warping <br /> slab surface spans between the beams. <br /> ■ y The maximum height of the shell roof is <br /> t„ about 25 feet. The dimensions and <br /> csarax , reinforcing of the concrete-framing <br /> members are not known. However, <br /> ,Y based on visual observation and past <br /> ■ �; �� experience with this type of structure, the <br /> beams and columns are likely heavily <br /> w x reinforced with steel reinforcing that may <br /> ` weigh on the order of 50 to 70 pounds <br /> per lineal foot. Clerestory windows form <br /> Atrium Space the wall between the typical roof <br /> structure and the higher atrium roof. <br /> First Floor <br /> The first floor framing over the basement is constructed of cast-in-place, one-way, pan and joist <br /> concrete framing. The joists span in the north-south direction of the building, and concrete girders <br /> r spanning in the east-west direction support them. The joists appear to have been constructed with <br /> pans that were 30" wide by 12" +/- deep, and the joist span is about 34 feet. Additional columns <br /> between the basement and first floor were added to reduce the floor framing span from that used <br /> above for the roof at some locations. The girders were not visible, but over the existing lanes they <br /> span the full 67 feet and are very likely deeper than the pan slab system and heavily reinforced. The <br /> . area outside the basement is constructed as a concrete slab-on-grade. <br /> Basement <br /> ■ The basement area is approximately 290' by 130' in plan. It is constructed as a concrete slab-on- <br /> grade. The area was used as a bowling alley, and there are 14"wide by 10" deep trenches at about <br /> 11' centers. The foundation walls are cast-in-place concrete. The basement is about 15 to 16 feet <br /> below the first floor. <br /> 11 <br />