Incorporating Slab/Underlying Layer Interaction into the Concrete Pavement Analysis Procedures (2017)

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APPENDIX C USER’S GUIDE TO SOFTWARE FOR MODIFIED MODELS The developed alternative models for the AASHTO M-E procedure are immediately accessible to users through the use of a basic companion program to the AASHTO M-E software, specifically AASHTOWare Pavement M-E Design. The following guidelines detail how users can install this software and use it to analyze existing AASHTO M-E projects to determine the effect of slab-base interaction on pavement performance. C.1. Program installation After opening the Software for Modified Models folder containing the research products within Windows Explorer, double click on the "setup.exe" file. The screen shown in Figure C-1 will appear. Figure C-1. Companion program installation screen Upon seeing the screen in Figure C-1, click "Next". The Installation Wizard will prompt you to select a destination directory for the program.

C-2 Figure C-2. Prompt to specify installation directory If the destination location is not already the root directory of one of the hard drives on your computer, it is recommended to change the directory using the “Browse” option. After that, a confirmation screen, shown in Figure C-3, will appear. Figure C-3. Confirming installation directory

C-3 Click "Next" on the confirmation screen in Figure C-3, and follow the on-screen instructions to complete the installation.

C-4 C.2. Running the companion program To run the companion program, the user should navigate to the installation directory and run the file “NCHRP_1_51.exe”. Upon running this program, the application opens with the main screen shown in Figure C-4. Figure C-4. Main program input screen To perform the analysis using this program, the user should provide location of the AASHTO M- E project directories. A sample of such a project directory is provided in the folder labeled “Example.” It is recommended to copy this directory on your computer hard drive. To select an existing AASHTO M-E project folder, mouse-click the button “Select Project Directory.” Upon clicking “Select Project Directory,” the user is prompted with a file explorer window (shown in Figure C-5) to select an AASHTO M-E project directory. In the figure below, the project “4_0217” has been selected from the Example folder.

C-5 Figure C-5. Locating AASHTO M-E project directory After the project folder is selected, the project name should appear next to the “Select Project Directory” button in the main program screen to confirm the project being analyzed. This is illustrated in Figure C-6.

C-6 Figure C-6. Confirmation of AASHTO M-E project directory in main input screen The main screen provides all of the necessary parameters for the alternative models. The program provides the recommended parameters, but the user may change them. If the user chooses to provide friction data for the entire service life of the project, the “User-provided” option should be selected for the Interface Deterioration Model. In this case, the text inputs for the initial nondimensional friction factor, Λ*, and friction degradation paramter, Cf, will disappear, as shown in Figure C-7.

C-7 Figure C-7. Effects of selecting “User-provided” in main input screen If the “User-provided” option for friction inputs of the interface friction model parameters has been selected, then the file explorer dialog window will be opened and a comma-separated text file with monthly non-dimensional friction data should be located, as shown in Figure C-8. The file should contain non-dimensional friction parameters for every month of the pavement life. The Example folder provides samples of such files for a project with a 20-year (240 months) design life:  “FrictionA.csv” contains constant through the entire performance period value of 0.001.  “FrictionB.csv” contains constant through the entire performance period value of 1000.  “FrictionC.csv” specifies a constant value of 1000 for the first 12 years and a constant value of 0.001 for the remaining time.  “FrictionD.csv” has values equal to 10 in January and February; 0.1 in March, April, and May; 0.001 from June through September; and 1 in October, November, and December. This pattern was repeated for every year during the analysis period.

C-8 Figure C-8. Locating user-defined friction file

C-9 C.3. Conducting analysis and reviewing program results To execute the alternative JPCP transverse cracking and faulting models, the user should click the button “Run Analysis” in the main program window. After running the alternative models for the project, the AASHTO M-E project directory will contain new intermediate and output files used by the alternative models. The performance prediction results, cracking and faulting, are stored in the following output files:  “151_JPCP_Cracking.CSV”, the final output for the modified JPCP Transverse Cracking model and  “151_JPCP_Faulting.CSV”, the final output for the modified JPCP Joint Faulting model. These output files are similar to JPCP_Cracking.CSV and JPCP_Faulting.CSV, the output files generated and used by the existing AASHTO M-E procedures. Column references are indicated in the first line of the comma-separated value (CSV) file, and all other lines indicate distress by month for every month of the project design life. After the execution of the models is completed, the rudimentary software will open these files using Windows Notepad program, as shown in Figure C-9a. However, it is more convenient to open the file in MS Excel program, which is shown in Figure C-9b. (a) (b) Figure C-9. Output files opened in Notepad and Excel