Title: Rigid Pavement Design Deficiencies
1Rigid Pavement Design Deficiencies
- Major shortcomings of JPCP designs based on
1972-1986 versions of the AASHTO Guide - inadequate joint load transfer,
- long joint spacing,
- erosion of base/subbase,
- poor subdrainage
- etc.
- Deterioration occurs early
- Rehabilitation needed
2Development of Supplemental AASHTO Design
Procedure for JPCP
- Serious deficiencies noted in 1986 AASHTO
procedure - Studies showed major flaws in base/subgrade
support procedures - No easy fixes
- Improved structural (3D finite element) model for
JPCP was developed to correct deficiencies
3Development, Validation, Adoption 1998
Supplemental Rigid Pavement Design Procedure
- Developed under NCHRP Project 1-30
- (University of Illinois at Urbana-Champaign)
- Validated under FHWA/LTPP research study
- (ERES Consultants/ARA)
- Adopted by AASHTO as Supplementary Rigid Pavement
Design Procedure (1998) - FHWA/LTPP - Supplementary Rigid Pavement Design
Spreadsheet (ERES Consultants/ARA)
4Only JPCP For Now
Jointed reinforced concrete pavement (JRCP) Contin
uously reinforced concrete pavement (CRCP)
Jointed plain concrete pavement (JPCP)
- Most constructed rigid
- pavement
- Basic design procedure
- developed
- Procedure field verified
- Limited field verification
51998 AASHTO JPCP Design Is Better
- Improved structural modeling
- Improved subgrade characterization
- Base course as structural layer
- Transverse joint spacing
- Climate at site is considered directly
- Shoulder type and slab width
- Joint faulting and cracking checks
6Use of LTPP Data to Verify1998 AASHTO Design
- Design procedure verified using field data from
LTPP - Inputs to 1998 AASHTO design model obtained
- Actual traffic log ESALs compared to predicted
log W (ESALs) - No significant bias found in predicting
serviceability of pavements in four climatic zones
7PRESENTATION OBJECTIVES
- What is the Rigid Pavement Design (RPD) Software?
- Development of RPD Software
- RPD Software Features and Capabilities
- How To Use The RPD Software
- Who Should Use the RPD Software and Why
- How to Get the RPD Software
8Rigid Pavement Design Spreadsheet Features
Information sheet containing spreadsheet User
Guide
9Rigid Pavement Design Spreadsheet Features
Command buttons for easy navigation between sheets
10Rigid Pavement Design Spreadsheet Features
Command button links to reference tables
11Rigid Pavement Design Spreadsheet Features
Joint spacing and edge support conditions are
direct inputs
12Rigid Pavement Design Spreadsheet Features
Climatic properties are direct inputs in the
supplemental rigid pavement design
True subgrade k-value is used (not adjusted for
top-of-base)
13Rigid Pavement Design Spreadsheet Features
Easy links to sensitivity analysis for various
design inputs
14Rigid Pavement Design Spreadsheet Features
Project data can be saved in rows and exported to
the main sheets
15Rigid Pavement Design Spreadsheet Features
Sensitivity Analysis plot displays inputs held
constant
16Rigid Pavement Design Spreadsheet Features
Results sheet can be viewed on screen or can be
printed
17Rigid Pavement Design Spreadsheet Features
Calculation sheet shows all calculations and
displays design traffic for different slab
thicknesses
18Rigid Pavement Design Spreadsheet Features
Faulting Check sheet used to estimate faulting
over design life for doweled and nondoweled
pavements
19PRESENTATION OBJECTIVES
- What is the Rigid Pavement Design (RPD) Software?
- Development of the RPD Software
- RPD Software Features and Capabilities
- How To Use The RPD Software
- Who Should Use the RPD Software and Why
- How to Get the RPD Software
20Systems Requirements
- IBM PC running
- Microsoft Office 95 or 97 or
- Microsoft Excel 7.0
21Using The RPD Software
- Copy the Rigid Pavement Design (RPD) Software
spreadsheet to the hard drive - The RPD software cannot be run from the floppy
drive - Open the RPD spreadsheet using Microsoft Excel
22Using The RPD Software
Click on Enable Macros to allow execution of
spreadsheet macros
23Using The RPD Software
Click on Input Form to access the main sheet
24Using The RPD Software
Enter General Information for the project as
shown below
25Using The RPD Software
Scroll down to enter Serviceability and PCC
Properties
26Using The RPD Software
Click on Table 14 for friction factors for
different base types
Enter Base Properties, Reliability, and Standard
Deviation
27Using The RPD Software
Click on Input Form to navigate back to the main
screen
28Using The RPD Software
Enter Joint Spacing
Select Pavement Type and Edge Support Condition
29Using The RPD Software
Enter Climatic Properties for the design region.
Click on Table 15 for climatic properties for
major metropolitan areas in each State.
For the first run enter the approximate subgrade
k-value
30Using The RPD Software
Click on Calculate Traffic for traffic
calculation worksheet
31Using The RPD Software
After entering traffic design inputs click
Calculate
Click Export to Input Form
32Using The RPD Software
Click on Calculate on the main sheet to calculate
thickness for design inputs
Click on Calculate Seasonal k-Value for
calculating seasonally adjusted k-value
33Using The RPD Software
Enter number of months and subgrade k-value for
each season. Click Calculate.
34Using The RPD Software
Use the chart to estimate adjusted k-value for
fill layer above the subgrade and/or rigid layer
beneath the subgrade
35Using The RPD Software
Click on Calculate on the main sheet to
recalculate thickness for design inputs with the
adjusted k-value
36Using The RPD Software
Enter thickness for sensitivity analysis
Click Slab Thickness Sensitivity for sensitivity
analysis of design traffic to slab thickness
Click on radial buttons for sensitivity analysis
of design traffic to different design inputs
37Using The RPD Software
38Using The RPD Software
39Using The RPD Software
Click on Faulting Check to perform checks for
doweled and nondoweled faulting
40Using The RPD Software
Enter dowel diameter and other design inputs for
doweled pavements
41Using The RPD Software
Click on FI Table or Drainage Coeff. Table for
tables containing information regarding these
inputs
Click Calculate to obtain estimated faulting at
end of design life
Click Results to view and print results
42Using The RPD Software
Enter design inputs for nondoweled faulting check
and click Calculate
Click Corner Break Check to perform top-down
cracking analysis
43Using The RPD Software
The critical values for joint faulting can be
changed by entering the appropriate values below
44Using The RPD Software
On the Corner Break Check worksheet enter the
built-in temperature gradient related to
construction curling and moisture gradient
45Using The RPD Software
Use one of six charts provided to estimate
tensile stress at top of slab from total
effective negative temperature differential
46Using The RPD Software
The tensile stress at the top of the slab is less
than the bottom up tensile stress for which the
pavement is designed
47Using The RPD Software
Results sheet can be viewed on screen or can be
printed
Click Save Data to save the design information
entered
48Using The RPD Software
Enter ID for saving data and click OK
49Using The RPD Software
All design information is saved in rows with the
first column corresponding to the data set ID
Select appropriate row and click Export to export
design information from this sheet to main sheet.
This sheet can be accessed by clicking on
Retrieve Data on the main sheet.
50PRESENTATION OBJECTIVES
- What is the Rigid Pavement Design (RPD) Software?
- Development of the RPD Software
- RPD Software Features and Capabilities
- How To Use The RPD Software
- Who Should Use the RPD Software Why
- How to Get the RPD Software
51Users of the RPD Software
- State and Provincial Highway Engineers
- Consulting Engineers
52Benefits of Rigid Pavement Design Software
- Provides key answers not previously addressed
- How do I adequately characterize the subgrade
support? - What is the best base type for the conditions?
- What is the optimum joint spacing?
- Will this pavement fault or have corner breaks?
53PRESENTATION OBJECTIVES
- What is the Rigid Pavement Design (RPD) Software?
- Development of the RPD Software
- RPD Software Features and Capabilities
- How To Use The RPD Software
- Who Should Use the RPD Software Why
- How to Get the RPD Software
54Get Use The Software
- Order software
- -- Through LTPP homepage
- www.tfhrc.gov
- -- Through LTPP customer service
- Call 865-481-2967