Civil Engineering Reference
In-Depth Information
Round forms for grandstand support
columns at The Texas Motor
Speedway, Fort Worth, Texas.
(Courtesy of EFCO Corp.)
coincides with the bar diameter in eighths of an inch. Bars were formerly manufactured in
both round and square cross sections, but today all bars are round.
The #9, #10, and #11 bars have diameters that provide areas equal to the areas of the
old 1-in.
1
8
1
8
1
4
1
4
1-in. square bars,
-in.
-in. square bars, and
-in.
-in. square bars,
1
2
1
2
respectively. Similarly, the #14 and #18 bars correspond to the old
-in.
-in. square
bars and 2-in.
2-in. square bars, respectively. Table A.2 (see Appendix) provides details
as to areas, diameters, and weights of reinforcing bars. Although #14 and #18 bars are
shown in this table, the designer should check his or her suppliers to see if they have these
very large sizes in stock. Reinforcing bars may be purchased in lengths up to 60 ft. Longer
bars have to be specially ordered. Normally they are too flexible and difficult to handle.
Welded wire fabric is also frequently used for reinforcing slabs, pavements and
shells, and places where there is normally not sufficient room for providing the necessary
concrete cover required for regular reinforcing bars. The mesh is made of cold-drawn
wires running in both directions and welded together at the points of intersection. The
sizes and spacings of the wire may be the same in both directions or may be different, de-
pending on design requirements. Wire mesh is easily placed, has excellent bond with the
concrete, and the spacing of the wires is well controlled.
