Highway Engineering

Structural Design of Pavement Thickness 245

40

35

30

25

20

15

100 200 300

Basic slab thickness (50%

probability) in mm

Correction to basic slab

thickness in mm (minus)

Figure 8.11Negative

correction to slab

thickness to make

allowance for

existence of tied

shoulders. (Crown

copyright 1987)

Cumulative traffic (msa)^

0.1 1 10 100

Slab thickness without tied

shoulder (mm)

50

150

0

100

200

250

300

Slab thickness with tied

shoulder (mm)

300

250

200

150

R = 0 mm^2 /m

R = 636 mm^2 /m^

Figure 8.12Design thicknesses for jointed concrete pavement (M=68 MPa). (Crown copyright
1987)