Huawei Y360-U03 Faq page 15

Rigid Pavement Design Example
Step 2 - Determine the subgrade resilient modulus (M
M = 1200 * CBR
r
M = 1200 * 5
r
M = 6000 psi
r
Step 3 - Determine the composite modulus of subgrade reaction (k
Starting with the given subbase thickness (D
modulus (E ) curve of 30,000 psi (Item 304 Aggregate Base from Figure 301-1). From this point on the
SB
30,000 psi curve, a line is projected to the right for future intersection. Similarly, from the 6" subbase
thickness (D ), a line is projected down to the subgrade resilient modulus (M
SB
this point on the 6000 psi curve, a line is projected to the right to the turning line and then projected up to
intersect with previously projected line. This intersection results in a composite modulus of subgrade
reaction (k ) of 335 pci.
c
Step 4 - Determine the effective modulus of subgrade reaction (k) using Figure 301-3.
Using the composite modulus of subgrade reaction (k
bottom. Project a line from 335 pci up to LS = 1.0 (from Figure 301-1 for Item 304 Aggregate Base).
Then project a line straight across to the vertical axis. This results in an effective modulus of subgrade
reaction (k) of 110 pci.
Step 5 - Determine the thickness of the concrete slab using Figures 302-2 and 302-3.
Figure 302-2 is used to solve for the match line number using the following information:
Effective modulus of subgrade (k) = 110 pci (Step 4)
Concrete elastic modulus (E
Concrete modulus of rupture (S'
Load Transfer Coefficient (J) = 2.7 (Figure 301-1)
Drainage coefficient (C
The resulting match line number is then used on Figure 302-3, along with the following information, to
solve for the design slab thickness (D).
Design serviceability loss (PSI) = 1.7 (Figure 201-1)
Reliability = 85% (Figure 201-1)
Overall standard deviation = 0.39 (Figure 201-1)
18-kip equivalent single axle load = 17.8x10
Therefore: design slab thickness (D) = 10 inches
Page 2
) of 6", a line is projected up to the subbase elastic
SB
) = 5,000,000 psi (Figure 301-1)
c
) = 700 psi (Figure 301-1)
c
) = 1.0 (Section 205.2)
d
6
Reference Section
) using the formula given in Section 203.1.
r
) using Figure 301-2.
c
) determined in Step 3, enter the chart on the
c
ESAL (Step 1)
302-1
July 2016
302
) curve of 6000 psi. From
r