Construction Databook Construction Materials and Equipment, 2nd edition_中.pdf

242 Section 4
Southern Pine Design Values—Span Tables (Continued)
Maximum spans given in feet and inches
SOUTHERN PINE SPAN TABLES - ALLOWABLE STRESS DESIGN Inside to inside of bearings
Table 8 Wet-Service Floor Joists
Design Criteria: Deflection - limited to span in inches divided by 360 (live load only).
Strength - based on 40, 60, or 100 pounds per square foot (psf) live load, plus 10 psf dead load.
Size (inches) and Spacing (inches on center)
2x6 2x8 2x10 2x12
Grade Live Load 12"oc 16"oc 24"oc 12"oc 16"oc 24"oc 12"oc 16"oc 24"oc 12"oc 16"oc 24"oc
40 psf 10-7 9-7 8-5 13-11 12-8 11-1 17-9 16-2 13-6 21-7 19-8 16-1
GOpsf 9-3 8-5 7-4 12-2 11-1 9-7 15-6 13-11 11-5 18-10 16-7 13-7
100 psf 7-9 7-1 6-1 10-3 9-4 7-8 12-10 11-1 9-1 15-4 13-3 10-4
40psf 10-4 9-5 7-10 13-8 12-5 10-2 17-5 15-10 13-1 21-2 18-10 15-5
60 psf 9-1 8-1 6-8 11-11 10-6 8-7 15-2 13-7 11-1 18-5 15-11 13-0
100 psf 7-6 6-6 5-3 9-8 8-4 6- 10 12-6 10-10 8-10 14-8 12-8 10-4
40 psf 9-4 8-1 6-7 11-11 10-3 8-5 14-0 12-2 9-11 16-8 14-6 11-10
60 psf 7-11 6-10 5-7 10-0 8-8 7-1 11-10 10-3 8-5 14-1 12-3 10-0
100 psf 6-3 5-5 4-5 8-0 6-11 5-8 9-5 8-2 6-8 11-3 9-9 8-0
Table 9 Rafters - Drywall or No Finished Ceiling - Construction Load (Co = 1-25)'
Design Criteria: Deflection - limited to span in inches divided by 240 or 180 (live load only).
Strength - based on 20 pounds per square foot (psf) live load, plus 10 psf dead load.
Size (inches) and Spacing (inches on center)
2x6 2x8 2x10 2x12
Grade Deflection 12"oc 16"oc 24"oc 12"oc 16"oc 24"oc 12"oc 16"oc 24"oc 12"oc 16"oc 24"oc
240 15-9 14-4 12-6 20-10 18-11 16-6 26-0* 24-1 21-1 26-0* 26-0* 25-2
180 17-4 15-9 13-9 22-11 20-10 17-9 26-0* 25-10 21-1 26-0* 26-0* 25-2
240 15-6 14-1 12-3 20-5 18-6 15-10 26-0 23-2 18-11 26-0* 26-0* 22-2
180 17-0 15-1 12-3 22-5 19-5 15-10 26-0* 23-2 18-11 26-0* 26-0* 22-2
240 13-6 11-8 9-6 17-2 14-10 12-1 20-3 17-6 14-4 24-1 20-11 17-1
180 13-6 11-8 9-6 17-2 14