Page 249 - Bridge and Highway Structure Rehabilitation and Repair

224 SECTION 2 STRENGTHENING AND REPAIR WORK

Figure 5.22 Stage concrete deck construction for long spans (density of wet concrete 3 160 pcf).
4. The following combinations are added to AASHTO LRFD bridge design code:
For strength I condition use
• All dead load of bridge components 4 wet concrete symmetric or unsymmetric pours
(DC1)
• Utilities (DC2)
• Construction equipment (CE1)
• Construction material such as screed (CE2)
• Construction live load, such as moving trolleys and deck finishing machines (CLL).

3 0.9 to 1.25
p
5. General dtrength 1 construction live load combination is:
(DC1 4 DC2) 4 1.5 (CE1 4 CE2) 4 1.5 (CLL).
p
• Stage 1 symmetric pattern of deck pour is assumed.
(DC1 pour-1 4 DC2) 4 1.5 (CE1 4 CE2) 4 1.5 (CLL)
p
• Stage 2 symmetric pattern of deck pour is assumed.
(DC1 pour-2 4 DC2) 4 1.5 (CE1 4 CE2) 4 1.5 (CLL)
p
• Stage 3 symmetric pattern of deck pour is assumed as shown in Figure 5.22.
(DC1 pour-3 4 DC2) 4 1.5 (CE1 4 CE2) 4 1.5 (CLL)
p
6. Alternate non-symmetric deck pour:
Nonsymmetric pattern of deck pour is assumed. Pattern to be provided by contractor and
will vary for each project.
( DC1 nonsym pour 4 DC2) 4 1.5 (CE1 4 CE2) 4 1.5 (CLL)
p
7. For strength III condition, use wind on superstructure including forming:
General construction wind load combination: Wind on superstructure (WS)
(DC1 4 DC2) 4 1.5 (CE1 4 CE2) 4 1.4 (WS)
p
• Stage 1 symmetric pattern of deck pour is assumed.
(DC1 4 DC2) 4 1.5 (CE1 4 CE2) 4 1.4 (WS)
p pour-1
• Stage 2 symmetric pattern of deck pour is assumed.
(DC1 4 DC2) 4 1.5 (CE1 4 CE2) 4 1.4 (WS)
p pour-2
• Stage 3 symmetric pattern of deck pour is assumed.
(DC1 4 DC2) 4 1.5 (CE1 4 CE2) 4 1.4 (WS)
p pour-3