There are different types of pavement, highways, streets and local roads and parking lots, and each require a different design method. This presentation explains through the differences and then goes into detail specifically as to the method for designing concrete parking lots. The presentation ends with a brief discussion of the "new realities" in paving as concrete and asphalt are now essentially equal on first costs.

1. Proper Concrete
Design Methodology
Roger Faulkner, PE
Director of Engineering & Promotion
Ohio Concrete

2. Overview
 TYPES OF PAVEMENT
 ASSOCIATED DESIGN METHODS
 PARKING LOT DESIGN
 PAVING – “The New Realities”

3. TYPES OF PAVEMENT
 Highways
Design Speed: 55 mph and greater
High Frequency of Heavy Truck Loads
 Streets and Local Roads
Design Speed: 25 mph to 45 mph
Low to Medium Frequency of Heavy Truck Loads
 Parking Lots and Drives
Design Speed: Typically Less than 15 mph
Minimal (or None) to Low Frequency of Heavy Truck Loads

4. DESIGN METHODS
 Highways
Linear Pavement – 2 or more lanes wide
Transverse Joints - Dowels
Edge Support – Tied Shoulders
Concrete Design Thickness – 9” or greater
 AASHTO 1993 Highway Design Guide
ODOT Pavement Design Manual
ACPA “WinPAS” Software

5. DESIGN METHODS
 Streets and Local Roads
Linear Pavement – 2 or more lanes wide
Transverse Joints – Dowels if Needed
Edge Support – Curb and Gutter or widened lane
Concrete Design Thickness – 6” to 8”
 ACPA
 “StreetPave” Software

6. DESIGN METHODS
 Parking Lots and Drives
Complex Area Pavement – Width Varies
Joints – Square Panels or Length to Width <1.25
Edge Support – Integral Curb or Thickened Edge
Concrete Design Thickness – 4” to 8”
 American Concrete Institute
ACI 330R-08 – “Guide for the Design and
Construction of Concrete Parking Lots”

7. PARKING LOT DESIGN
 ACI 330R-08
 Section 3.6 –
“Thickness Design”
 Plain Concrete
Pavement

8. PARKING LOT DESIGN
 ACI 330R-08, Section 3.6
 Traffic Categories

9. PARKING LOT DESIGN
 Subgrade Support
 Typ. K=100 psi/in.
 Concrete Flexural Strength
 MOR (psi) = 10 x Square Root of f’c
 For f’c= 3500 to 5000 psi
MOR = 600 to 670 psi
 Table 3.4, Recommended 20 Year
Design Thicknesses, with no dowels

10. PARKING LOT DESIGN

11. PARKING LOT DESIGN
 Steel Reinforcement
 Per 3.8.1 – “The use of distributed steel
reinforcement will not add to the load-carrying
capacity of the pavement and should not be
used in anticipation of poor construction
practices.”
 Replaced with Shorter Joint Spacings

12. PARKING LOT DESIGN
 Joint Spacing
 Per Section 3.7
Joint Patterns should be approx. square
Length Not > than 125% of Width
Spacing = 2 x thickness in Feet
 Jointing Pattern can be used to delineate
parking lanes and parking stalls

13. PARKING LOT DESIGN
 Tie-Bars
 Per 3.8.3 – Tie only the first longitudinal joint
from the pavement edge to keep the outside slab
from separating
 Tie Centerline Joints of Entrance Drives
No. 4, ½” dia. – Typ. 24” long (See Table 3.7)
30” spacing

14. PARKING LOT DESIGN
 Dowels
 Per 3.8.2 – Dowels generally not needed for
parking lots
 Per Table 3.4 – Category D Thickness can be
reduced 1” to 7”, if dowels are used

15. PARKING LOT DESIGN
 Table 3.4 of ACI 330R-08
Developed using
ACPA“StreetPave” Computer
Program MC003
 It is a pavement design tool for
low volume roads (streets &
local roads)
 It is based on the PCA’s
pavement thickness design
methodology
 PCA assesses adequacy of
concrete thickness using both
fatigue and erosion criteria

16. PARKING LOT DESIGN
 Engineering Services Center “ESC”
 CAD parking lot and intersection layout
Concrete Mix Design
Pavement Thickness and Joint Spacing
 FREE Service!

17. Paving - “The New Realities”
 Concrete and Asphalt have reached parity on
Initial Cost
 ODOT Initiated Alternate Pavement Bids
 Those Projects Yielded HUGE Cost Savings

18. ODOT Alternate Bid Projects
 5 Projects Bid in 2009 w/ Alternate Pavement Bids
 State’s Estimate for the 5 Projects - $405 Million
 Total Award for the 5 Projects - $345 Million
 $60 Million Cost Savings or approx. 15%
 Non-Alternate Bid Projects
 3 Asphalt Only - $170 M Est., $157 M Award
 $13 Million Savings – Ave. 7% Cost Savings
 Alternate Bids Yield TWICE the Costs Savings!

19. ODOT Alternate Bid Projects
 Key Aspects of Alternate Bid Process
 Increased Competition
 More bidders
 Plus, competition between Asphalt and Concrete Industries
 No Material Price Adjustments
 ODOT Proposal Note 115, Price Adjustment Exclusions
 Contractor Required to Submit Prices for Both
ODOT chooses the alternate

20. ODOT Drafts New Policy
 Projects require an LCCA for both concrete and
asphalt pavement alternates
If LCCA’s >10%
Alternate with Lower LCCA is selected alternate
An Updated LCCA Required before Final Tracings
• If LCCA’s still >10% - project bid with original alternate
• If LCCA’s <10% - plans modified to bid with both concrete and
asphalt pavement alternates
If LCCA’s <10%
Plans developed to bid for both concrete and asphalt alternates

21. Questions?

22. Proper Concrete
Design Methodology
THANK YOU !