Dan King, E.I.T. Iowa Concrete Paving Association

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1 Dan King, E.I.T. Iowa Concrete Paving Association

2 OUTLINE Street and Highway Design with WinPAS AASHTO 93 design method SUDAS pavement design ACI Concrete Parking Lot Design Guide ACI Industrial & Trucking Facility Design Guide Previous Image: GCC Ready Mix

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4 WinPAS DESIGN If Eric hasn t already convinced you to use PavementDesigner... Free-to-use Easily accessible in your web browser Modern, streamlined interface Links to a library of supplemental resources...pavementdesigner is a fantastic new tool! WinPAS (AASHTO design) can be a useful pavement design tool as well

5 WinPAS DESIGN WinPAS = Windows Pavement Analyst Software Electronic version of AASHTO 1993 Pavement Design Guide For both concrete and asphalt pavements Although it is not included in PavementDesigner.org, AASHTO design is still used by many agencies across the country Basis for SUDAS pavement design

6 WinPAS DESIGN AASHTO 93 Design A mostly empirical design procedure based on performance of the AASHO road test sections Has been modified over the years to account for more variables and concepts AASHO Road Test, 1950 Q: Where at?

7 WinPAS DESIGN AASHTO 93 Design Uses many of the same design inputs as PavementDesigner (PCA Method/StreetPave) Some different, unique concepts between the two The equations/models may handle same inputs differently AASHO Road Test, 1950 Ottawa, IL (I-80)

8 WinPAS DESIGN Some differences with WinPAS/AASHTO design: Traffic level characterized by ESALs Equivalent single axle loads Based on load equivalency factors for different types of trucks Only considers a particular number of load repetitions to failure, calibrated based on AASHO road test results No modeling of fatigue or erosion like in PavementDesigner

9 WinPAS DESIGN Some differences with WinPAS/AASHTO design: End of pavement life: terminal serviceability index Instead of defining % slabs cracked Joint spacing does not play any role in thickness design Some different terms for reliability, standard deviation

10 WinPAS DESIGN When might you want to use WinPAS/AASHTO pavement design? It does have well-known limitations But it s also been used successfully for many years and is well-understood by many of its practitioners Both for concrete and asphalt The closer you get to the conditions of the AASHO road test, the more accurate the procedure will be

11 WinPAS DESIGN When might you want to use WinPAS/AASHTO pavement design? Climate, materials and soils in Iowa are similar to those at the road test site in northern Illinois Designing for low-to-medium traffic volumes may be closer to road test conditions than higher volume traffic Good understanding of the design procedure and customized local design inputs & commentary SUDAS Pavement Thickness Design

12 WinPAS DESIGN SUDAS Pavement Thickness Design Section 5F-1 in design manual Based on AASHTO 93 design methods for both concrete and asphalt pavements Provides full commentary and explanation of AASHTO 93 input values, including recommendations for representative Iowa values

13 WinPAS DESIGN SUDAS Pavement Thickness Design Contains basic design tables & sample calculations for simple designs Can also plug recommended inputs directly into WinPAS to perform a custom pavement design Allows for easy comparison of equivalent AASHTO 93 concrete & asphalt designs for local conditions

14 WinPAS DESIGN Walk-through design example

15 WinPAS DESIGN Other capabilities in WinPAS Concrete overlays AASHTO 93 concrete overlay design can be a bit out of date PavementDesigner + BCOA-ME are likely better tools Life cycle cost analysis Full control of input costs, discount rates, etc. Not included in PavementDesigner

16 WinPAS DESIGN Final thoughts on thickness design for PCC streets and highways Different design procedures can be effective and useful tools, provided: Good understanding by practitioner Applicable to situation you are designing for Quality of data and inputs Ability to customize input values

17 WinPAS DESIGN In the future, street/highway design will continue to transition to more mechanistic procedures like Pavement ME State agency-level: gradually phasing in now across US Local level: implementation is a bit farther out, could be quite different

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19 ACI PARKING LOT DESIGN ACI 330R-08: Guide for the Design and Construction of Concrete Parking Lots Available through ICPA/IRMCA Thickness design components are fully incorporated into PavementDesigner.org Same StreetPave/PCA

20 ACI PARKING LOT DESIGN PavementDesigner.org:

21 ACI PARKING LOT DESIGN Some things to consider for design of concrete parking lots: Traffic Subbase & Subgrade Jointing Reinforcement

22 ACI PARKING LOT DESIGN Traffic Inputs Choose a category based on chart below Each category is available in PavementDesigner Traffic category dictates assumed axle load distribution for thickness design

23 ACI PARKING LOT DESIGN Subbase & Subgrade Just like with concrete streets and roads, uniformity of support is more important than strength Subbase more useful to promote good drainage & ensure stable working platform on weak soils Surface Water Cracking from nonuniform support from differential soil Adsorption movement. Water Capillary

24 ACI PARKING LOT DESIGN Jointing Contraction joints Timely sawing necessary to prevent random cracking Recommended minimum T/4 saw depth with conventional saws Recommended 1 to 1 1 saw cut depth with earlyentry 4 saws Filling/sealing joints May not be necessary if you have a drainable subbase Recommended 1/8 saw cut width if leaving unsealed

25 ACI PARKING LOT DESIGN Jointing Recommended joint spacing Smaller slabs help control cracking, mitigate curling stresses Panel length should not exceed width by more than 25% (square slabs) Guidelines in ACI guide currently a bit longer than what PavementDesigner may show as an output

26 ACI PARKING LOT DESIGN Reinforcement Distributed steel reinforcement is not necessary. Stay within recommended joint spacings from table Steel can help prevent cracks from opening Construction difficulties... Proper joint spacing and incorporating subbase may be more proactive way to prevent cracking Consider fiber-reinforced concrete as an alternative to steel Dowel bars generally only needed for load transfer in case of heavy, one-way truck traffic

27 ACI PARKING LOT DESIGN Tie bars recommended for outermost row of panels around the perimeter: Tension Ring Exception for integral curb Also recommended for centerline joint on drive lanes, etc.

28 ACI PARKING LOT DESIGN In summary: PavementDesigner makes concrete parking lot thickness design simple and easy The ACI guide is still a valuable resource to help with some of the other unique aspects of concrete parking lot design

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30 INDUSTRIAL & TRUCKING FACILITY DESIGN ACI 330.2R-17: Guide for the Design and Construction of Concrete Site Paving for Industrial and Trucking Facilities Brand new in 2017! Available through ICPA/IRMCA Thickness design components use combination of StreetPave/PCA

31 INDUSTRIAL & TRUCKING FACILITY DESIGN Many of the general principles in this guide follow those of regular parking lots Industrial-type facilities can have unique traffic loadings: Not only heavy trucks, but forklifts, telehandlers, lulls...

32 INDUSTRIAL & TRUCKING FACILITY DESIGN Thickness design tables are available for over-the-road trucks and various types of lift trucks:

33 INDUSTRIAL & TRUCKING FACILITY DESIGN Because of nature of loading at these facilities, dowel bars may be needed for load transfer Two-directional doweling for all-way movements Guidance provided on use of alternative dowel bar types, such as square or plate dowels May better handle stresses, shrinkage, and lateral movement than round dowels when two-directional doweling is needed Images: PNA Construction

34 THANK YOU! ICPA Workshop, 1980