Title:
The Un-Shored Composite Slab on Metal Deck Part II, Ineffective Contract Document Requirements
Author(s):
Eldon Tipping and Bryan M. Birdwell
Publication:
Symposium Paper
Volume:
338
Issue:
Appears on pages(s):
65-74
Keywords:
beams, deflection, girders, level, mandatory, specification, metal deck SP-338: Ward R. Malisch Concrete Construction Symposium 65
DOI:
10.14359/51724729
Date:
3/1/2020
Abstract:
This is the second of a three-part series, the goal of which is to provide the designer and contractor with
tools necessary to produce level deflected slabs on metal deck. This second part explores the role ineffective and
incorrect use of ACI and AISC documents plays in designer attempts to provide his client with level deflected slabs
on metal deck. Project documents often incorrectly reference ACI guide documents such as ACI 302, attempting to
make their content mandatory, when that is not intended by ACI. The ACI prohibition of using guide document
content without restating in mandatory language is presented and discussed. Reference is often made in design
documents to the AISC Code of Standard Practice for floor elevation when the Code is silent concerning the
elevation of all elements excepting that of column base plate elevation. AISC tolerances impacting floor levelness
are presented and discussed. Virtually all supporting structural steel floor framing systems are comprised of a
collection of secondary members (beams) which transfer gravity loads to primary members (girders) which
ultimately transfer these gravity loads to vertical elements and finally to foundations. The collection of floor
framing members contains some combination of un-cambered steel beams/girders and those with fabricated camber
to off-set anticipated deflection of the member when subjected to the weight of concrete. The deflection of those
members will vary depending on member stiffness and the resistance of connections to end rotation. The
ineffectiveness of the common designer requirement that concrete be added until “the floor is level” is presented and
discussed in detail.