Design Considerations for Economical Formwork - Simplified Design of Reinforced Concrete Buildings - page 264

• Use the same shape as often as possible throughout the entire building. Square, rectangular, or round
columns are the most economical; use other shapes only when architectural requirements so dictate.

9.5.3 Walls

• Use the same wall thickness throughout a project if possible; this facilitates the reuse of equipment, ties,
and hardware. In addition, this minimizes the possibilities of error in the field. In all cases, maintain
sufficient wall thickness to permit proper placing and vibrating of concrete.

• Wall openings should be kept to a minimum number since they can be costly and time-consuming. A few
larger openings are more cost-effective than many smaller openings. Size and location should be
constant for maximum reuse of formwork.

• Brick ledges should be kept at a constant height with a minimum number of steps. Thickness as well as
height should be in dimensional units of lumber, approximately as closely as possible those of the
masonry to be placed. Brick ledge locations and dimensions should be detailed on the structural drawings.

• Footing elevations should be kept constant along any given wall if possible. This facilitates the use of
wall gang forms from footing to footing. If footing steps are required, use the minimum number possible.

• For buildings of moderate height, pilasters can be used to transfer column loads into the foundation walls.
Gang forms can be used more easily if the pilaster sides are splayed as shown in Fig. 9-9.

x + 1”

x

Figure 9-9 Pilasters

9.6 OVERALL STRUCTURAL ECONOMY

While it has been the primary purpose of this chapter to focus on those considerations that will significantly
impact the costs of the structural system relative to formwork requirements, the 10-step process below should
be followed during the preliminary and final design phases of the construction project as this will lead to
overall structural economy:

(1) Study the structure as a whole.

(2) Prepare freehand alternative sketches comparing all likely structural framing systems.

(3) Establish column locations as uniformly as possible, keeping orientation and size constant wherever possible.