Page 216 - Civil Engineering Formulas

CONCRETE FORMULAS 151

falls outside the middle third, the pressure vanishes under a zone around the
heel, and pressure at the toe is much larger than for the other cases.
The variables in the five formulas in Fig. 5.4 are

2
P and P the pressure, lb/ft (MPa), at the locations shown
2
1
L and a dimensions, ft (m), at the locations shown
R the total downward force on the soil behind the retaining wall, lb (N)
v
R resultant, lb(N)
Earth
backfill
Stem
Stem
Front Back
K
Toe Heel
Heel
DC
B
A
Earth in front Footing or base
T- shape wall L-shape wall

Stem
Stem
Counterfort
Toe Toe
Heel

Reversed Counterfort wall
L-shape wall

Buttress
Buttress
Stem Stem

Toe
Toe Heel

Buttressed wall
(a)

FIGURE 5.4 (a) Six types of retaining walls. (b) Soil-pressure variation in retaining
walls. (Merritt-Building Construction Handbook, McGraw-Hill.)