Civil Engineering Reference
In-Depth Information
10
8
6
L
b
= 20 ft
φ
4
M
bn1
M
bn3
M
bn10
= 40
o
2
S
c
/S
b
= 4
0
-30
-20
-10
0
10
20
End Column Moment, M, kips-ft
Fig. A.58
End Column Moments at Backfill (φ = 40º, All Bays, L
b
=20 ft, S
c
/S
b
= 4)
10
8
6
L
b
= 20 ft
φ
4
M
en1
M
en3
M
en10
= 40
o
2
S
c
/S
b
= 4
0
-30
-20
-10
0
10
20
End Column Moment, M, kips-ft
Fig. A.59
End Column Moments at Expansion (
φ
= 40º, All Bays, L
b
=20 ft, S
c
/S
b
= 4)
The end column moments at the end of the backfill stage, shown in Fig. A.58,
are fairly comparable to their counterpart of the 20-ft bay frames with a column to
beam stiffness ratio of 1. The end column moments at expansion, however, are
substantially larger than their counterparts of the frames presented latterly. This of
course indicates that in addition to the expansion and contraction length of the
frames, the effect of lateral stiffness is also fairly pronounced in the development
of flexural stresses in the frame members due to the thermal movements.
