STRUCTURAL DESIGN FOR ARCHITECTURE

Structural Design for Architecture

Fig. 4.54 Plan arrangements for loadbearing-wall struc-

tures of reinforced concrete.

structural walls for stability. This is sometimes

the reason why a frame, as opposed to a flat-

slab structure is adopted.

The frame types which have been described

here are the most basic forms. Considerable

variation from these is possible although this

will normally increase the cost of the structure.

The simplest variation is the displacement of

individual columns from a strictly regular grid,

in order to accommodate some aspect of the

space-planning of the interior. If the displace-

ment is kept within one quarter of the span it

can be accommodated easily by strengthening

the structure locally. Another common vari-

ation is a small change in the level of a floor

over a short area of the plan; this too can be

easily accommodated in in situ reinforced

concrete, as can the ramps and stairs which

are required for access. More significant varia-

tions from the standard forms are illustrated in

Figs 2.8, 2.10 and 2.14.

Fig. 4.55 Plan arrangement for reinforced concrete

loadbearing-wall structure with one-way-spanning floor

slabs. Note that this conforms to the parallel-wall arrange-

ment which is typical of loadbearing wall-structures in all

materials.

4.4.2.5 Loadbearing-wall structures

The planning principles for reinforced concrete

loadbearing-wall structures are similar to those

which are used for masonry structures

although the arrangement of walls is normally

simpler because the greater flexural strength of

concrete eliminates the need for local stiffen-

ing to combat buckling. Three plan-forms are

commonly used: cross-wall and spine-wall,

with one-way-spanning floors, and cellular,

with two-way-spanning floors (Fig. 4.54 and

4.55). The spacing between the walls is kept as

uniform as possible so that the slab spans are

equal and maximum benefit is obtained from

continuity. The most economic spans are

around 5 m to 6 m. In cross-wall and spine-

140 wall structures, in which the loadbearing walls

Plan showing

layout of rooms

Plan showing

structural elements

Non-structural face panels

Non-structural partitions 1m 6.9 m

5m

2.5m

2.5 m

3.7 m

2.5 m

2.5 m

5m