CRSI |
ENGINEERING
DATA REPORT NUMBER 35 |
EFFICIENT AND ECONOMICAL REBAR DETAILS - PART 1 |
 A
SERVICE OF THE CONCRETE REINFORCING STEEL INSTITUTE
933 N. Plum Grove Rd., Schaumburg, Illinois 60173-4758 |
INTRODUCTION
One of the advantages of
reinforced concrete construction is the plastic ability of the concrete material to be
cast into any shape or form. The esthetics of a building, bridge, or other structure is
the result of the creative imagination of an Architect/Engineer team. Outstanding
achievement awards for creative designs are presented regularly by the Concrete
Reinforcing Steel Institute and other organizations that are interested in promoting
cast-in-place reinforced concrete construction.
Outstanding and innovative architectural design does not mean that the
economics of building the structure is ignored because most buildings are constructed to
an finite owners budget. Even as the Architect envisions the conceptual shape and end
design, he or she knows that the structure must be built in segments, pour by pour, story
by story, each portion in proper sequence and in a cost effective manner. However, in the
most simple or elaborate structures there are practical limitations to the shape and
lengths of the reinforcing bars which must fit into the frame members. In order to achieve
an economical concrete structure, it behooves the Architect/ Engineer to become familiar
with bar configurations that are troublesome and costly for the Rebar Fabricator to
fabricate and the Ironworker to place and tie. Unfortunately many inexperienced Rebar
Detailers often accept the details shown on the Engineers structural drawings and no
consideration is given to the degree of difficulty of fabricating and placing the rebar in
accordance with the details shown. The configurations shown on the design documents are
accepted and the same configurations unfortunately are repeated on the placing drawings.
The purpose of this Engineering Data Report is to inform the
Architect/Engineer team of several specific instances where configurations shown in
typical details could be improved upon in order to provide a more economical method of
furnishing, fabricating, and placing the required reinforcing steel.
Configurations, General
A good rule for the design team to follow is to keep
the rebar shapes and configurations as simple as possible. In addition, there are
practical limitations on bar length and fabrication width during the manufacture,
fabrication, and transportation to the jobsite. Producing mills roll reinforcing bars to a
standard stock length of sixty feet, and lengths in excess of sixty feet become a special
order item. After fabrication, the width of bent bars must also be considered for delivery
to the jobsite by truck. Special trucking permits, overwidth load permits, etc., can be
costly methods of shipping.
Configurations, Specific
The following details show bar configurations where
precise fabricating dimensions are difficult to maintain and are costly to place. The
suggested alternate details would result in a more economical fabrication and placement of
the rebar.
| 12 BAR COLUMN |
 |
  |
| Initial
Detail |
Suggested
Alternate Details |
© Copyright 1990 by the Concrete Reinforcing Steel Institute
