Geotechnical Engineering

DHARM

528 GEOTECHNICAL ENGINEERING

9°

a= 81°

Wall

3.6 m

b= 10°

Repture plane

x = 2.40 m

2.35 m

69°

f=line

f= 30°

(+)

= 42°

fd

fad=( – )

= 69°

Fig. 13.63 Rebhann’s construction for active thrust (Ex. 13.18)

Example 13.19: A retaining wall with a vertical back 5 m high supports a cohesionless backfill
of unit weight of 19 kN/m^3. The upper surface of the backfill rises at an angle of 10° with the
horizontal from the crest of the wall. The angle of internal friction for the soil is 30°, and the
angle of wall friction is 20°. Determine the total active pressure per lineal metre of the wall
and mark the direction and point of application of the thrust. Use Rebhann’s graphical method.

(S.V.U.—B.E. (Part-time)—Apr., 1982)

b= 10°

5m

Wall

a= 90°

20°

Pa

(+)

= 50°

fd

yad=( – )= 70°

70°

2.9 m

x=3m

f-line

Ground line

f= 30°

Rupture plane

yad= – = 90 – 20 = 70°°°

(^53) mm
Fig. 13.64 Rebhann’s construction for active thrust (Ex. 13.19)
H = 5 m φ = 30° δ = 20° β = 10° α = 90° γ = 19 kN/m^3
ψ = α – δ = 70°