Civil Engineering Reference
In-Depth Information
20
15
10
L
b
= 20 ft
φ
U
hn1
U
hn3
U
hn10
= 30
o
5
S
c
/S
b
= 1
0
0
0.05
0.1
0.15
0.2
Horizontal Retaining Wall Movement, U
h
, ft
Fig. B.19
Retaining Wall Movements at Backfill Stage (φ = 30º, All Bays, L
b
=20 ft, S
c
/S
b
= 1)
20
15
10
L
b
= 20 ft
φ
U
hen1
U
hen3
U
hen10
= 30
o
5
S
c
/S
b
= 1
0
0
0.05
0.1
0.15
0.2
Horizontal Retaining Wall Movement, U
h
, ft
Fig. B.20
Retaining Wall Movements at Expansion Cycle (
φ
= 30º, All Bays, L
b
=20 ft,
S
c
/S
b
= 1)
The lateral earth pressure developed in the retained soil mass at the end of the
last expansion cycle is shown in Fig. B.21. The top graphic in Fig. 7.10 of chapter
7 presents the lateral earth pressure for the same group of frames found at the end
of the backfill stage.
Fig. B.21 indicates that the lateral earth pressure at the end of the expansion cy-
cle developed in the soil mass retained by the single and 3-bay frames is nearly
equal to the Coulomb's active earth pressure, and the earth pressure loads pre-
scribed in national building codes. The earth pressure developed behind the 10-
bay frame, on the other hand, is comparable to lateral earth pressure at rest.
Comparing the lateral earth pressure found behind the 10-bay frame with a
length of 200 feet shown in Fig. B.21, to its counterpart developed behind the
