Page 283 - Bridge and Highway Structure Rehabilitation and Repair

258 SECTION 2 STRENGTHENING AND REPAIR WORK

6.5.5 Shear Capacity Rating of Steel Girders for Load Combinations
(Summary of steps refers to LRFD sections)
Compact and non-compact sections:
1. Strength limit states I and II.
2. Construction limit state and uncured slab.
3. For stiffened webs refer to Section 6.10.7.3.
4. For unstiffened webs refer to Section 6.10.7.2.
Interior panels of compact sections:
1. Refer to Section 6.10.7.3.3a.
2. Strength limit states I and II.
3. Uncured slab.
Interior panels of non-compact sections:
1. Strength limit states I and II.
2. Construction limit state and uncured slab.
3. Refer to Section 6.10.7.3.3b.
6.5.6 Evaluation of Defl ection
(Summary of steps refer to LRFD sections)
1. Service limit State II.
2. Refer to Section 6.10.3.2.
3. Control of permanent defl ection.
Compute C: D / t w
W
Compute k: k 3 5 4 5/ (d / D) 2
0
1 /
10.10 (Ek/F ) 2 D / t w
W
yw
1 /
1.38 (Ek/F ) 2 D / t w
W
yw
1.52 (Ek/F )
C 3 yw
(D / t ) 2
W w
V 3 0.58F D t
p
yw
W w
V 3 C V p
n
Both inventory rating and operating rating 9 1.0 for HL-93 loads.
Nominal shear resistance for unstiffened web (LRFD Section 6.10.7.2):
1 /
If 2.46 (E/F ) 2 9 D/ t w
yw
V 3 0.58 F Dt (Eq. 6.10.7.2-1)
n yw w
Service II limit state. Section 6.6.4.1.
f 6 ( )(f )
D
D
R
Let rating factor RF 3 1
( ) (f )
L LL 4IM
f 3 0.80 R R F yf LRFD 6.10.5.2
h
b
R

For tension flange load shedding factorR 3 1.0; LRFD 6.10.4.3.2 b
b
1 /
For compression fl ange, if2Dc/t (E/f ) 2, R 3 1.0; LRFD 6.10.4.3.2a
w
b
b
c
For homogeneous sections, R 3 1.0; LRFD 6.10.4.3.1
b
( ) 3 ( ) 3 1.0; Table 6-1
DC
DW
( ) 3 1.3 for inventory; ( ) 3 1.0 for operating.
L L