chapter 3 rigid pavement - DOT On-Line Publications - Department ...

BXAHPLB B:
The State elects to change their design by reducing.the joint
spacing to 30 feet.
Step 1 - Determine the anticipated joint movement.
AL is directly proportional to L;
decreases AL by 50 percent.
AL= 0.15 inch
Step 2 - Select width of uncompressed seal.
decreasing L by 50 percent
w 2 AL + (C, - C,)
> 0.15 f ( 0.55 - 0.20 )
2 0.15 i 0.35
2 0.43 inch
use W = 0.688 inch ( a larger size than necessary )
Step 3 - Select width of sawcut.
PC = c* + Install temr, - Min temx,
1
C Maximum temp - Min temp
Sc=(1-Pc)*W
Case 1: Installation temperature = 80'F
* (%a - Gin)
PC = 0.2 + [ ( 66 i- 76 ) * ( 0.55 - 0.2 ) ]
= 0.2 + ( 0.87 ) * ( 0.35 )
= 0.50
SC =(l- 0.5 ) * 0.688
= 0.344 inch
Case 2: Installation temperature = 40-F
PC = 0.2 + [ ( 26 + 76 ) * ( 0.55 - 0.2 ) ]
- 0.'2 + ( 0.34 ) * ( 0.35 )
= 0.32
SC =(l- 0.32 ) * 0.688
= 0.47 inch
3.3.8