Step 1: Launch KENPAVE. Step 2: Select LAYERINP

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1 Step 1: Launch KENPAVE Step 2: Select LAYERINP

2 Step 3: Click on File on the toolbar To set up a new data file click 'File' and 'New' and the filename 'Untitled' will appear on the label beneath 'File'. You can now proceed to input the necessary data. Step 4: Click on General on the toolbar TITLE: Enter any descriptive title of 68 characters or less. Commas are not allowed. MATL: Enter 1 if all of the materials we ll be using are linear elastic. NDAMA: Enter 0 since we don t want to do a damage analysis at this time. Later on, we may change this to 1 to determine how many load applications are needed to cause failure. NPY: Enter 1 since we will not be using seasonally-varying layer moduli. Eventually, we ll use moduli that vary throughout the year based on seasonal changes in temperature and moisture. NLG: Enter 1 because we will only have one load group. You can have as many as 12 different load groups. A load group consists of either a single wheel load, a dual wheel load, a tandem axle load, or a tridem axle loaf. DEL: Leave at the default of 0.001, which implies a numerical integration accuracy of 0.1%. NL: Enter 2 because 1 doesn t work. KENLAYER models the pavement system as one or several material layers overlying a semi-infinite halfspace. You must have at least one layer in addition to the halfspace, so two is the minimum number of layers you can have. You can have up to 19 different pavement layers.

3 NZ: Enter 1 because we re only going to request stress and deflection outputs at just one depth. You can obtain output at as many as 19 different depths. ICL: Leave at 80. If the program doesn t converge on a solution within 80 iteration, it stops. NSTD: Enter 5 to output vertical displacements and stresses. You can also choose 1 to output only vertical displacements or 9 to output vertical displacements, stresses, and strains. NBOND: Leave at 1 to use fully frictional layer interfaces. You could also choose 2 if one ore more interfaces are to be frictionless. NLBT: Leave at 1 since we re not doing a damage analysis. This entry specifies the number of layers for which a damage analysis will be performed based on the tensile strain at the bottom of the layer (which contributes to fatigue failure). NLBT: Leave at 1 since we re not doing a damage analysis. This entry specifies the number of layers for which a damage analysis will be performed based on the compressive strain at the top of the layer (which contributes to rutting failure). NUNIT: Leave at 0 for English units. You can also set it to 1 for SI units. Upon completion, click 'OK' to return to the Main Menu of LAYERINP. Step 5: Click on Zcoord on the toolbar

4 ZC: Enter the depth (in inches) at which you want to obtain stress/strain/deflection output. When the point is located exactly at the interface between two layers, the results are for the bottom of upper layer. If the results at the top of next lower layer are desired, a slightly larger z coordinate, say larger, should be used. Upon completion, click the 'OK' button to return to the Main Menu of LAYERINP. Step 6: Click on Layer on the toolbar TH: Enter the thickness of each material layer in inches. The last layer is infinite in thickness and need not be specified. PR: Enter 0.5 for incompressible materials. Suggested values are 0.35 for asphalt and granular materials and 0.45 for fine-grained soils. After typing the data in a cell, be sure to press Enter or the up or down arrow key to make it effective. You can delete a line (layer) by first clicking anywhere on the line to make it active, then pressing <Ctrl><Del>. The NL in the 'General' menu will be reduced automatically by 1. You can add a new line (layer) above any existing line (layer) by first clicking the cell in the existing line to make it active, then pressing <Ctrl><Ins>. A blank line will appear for you to enter the necessary data. The NL in the 'General' menu will increase automatically by 1. After completing this form, click 'OK' to return to the Main Menu of LAYERINP.

5 Step 7: Click on Moduli on the toolbar Step 8: Click on the Period1 button

6 E: Enter 3000 for the modulus of each layer. Upon completion, click the 'OK' button to return to the Layer Modulus of Each Period. Step 9: Click on Load on the toolbar LOAD: Enter 0 for a single axle with a single tire (i.e., one contact patch). Other possible choices are 1 for a single axle with a dual wheel (two contact patches), 2 for tandem axles with dual wheels (four contact patches), and 3 for a tridem axle with dual wheels (six contact patches). See Figure 3.8 in the textbook. CR: Enter 6.01 for the radius of the contact patch (in inches). CP: Enter 88 for the contact pressure (in psi). YW: Enter 0 since there is only one contact patch. This is the center-to-center spacing between the two dual wheels. See Figure 3.8 in the textbook. XW: Enter 0 since there is only one axle. This is the center-to-center spacing between the axles. See Figure 3.8 in the textbook. NR or NPT: Enter 6 for the number of points in the horizontal plane at which you want outputs. You can delete a line (layer) by first clicking anywhere on the line to make it active, then pressing <Ctrl><Del>. The NL in the 'General' menu will be reduced automatically by 1.

7 You can add a new line (layer) above any existing line (layer) by first clicking the cell in the existing line to make it active, then pressing <Ctrl><Ins>. A blank line will appear for you to enter the necessary data. The NL in the 'General' menu will increase automatically by 1. After completing this form, click 'OK' to enter the auxiliary form where you enter the coordinates of the output points. Step 10: Fill in the auxiliary form RC: Enter the radial offset for each of the 6 output locations (0, 12, 24, 36, 48, 60) in inches. After completing this form, click 'OK' to return to the load information form, then click 'OK' to return to the Main Menu of LAYERINP. Step 11: Click on Save As to save the data to a new file Name it Problem4 or something like that. Since this program is DOS-based, you probably can t use file names with embedded spaces or filenames with more than 8 characters (not counting the file extension, which will always be.dat ). Step 12: Click on Exit Step 13: Click on KENLAYER to perform the calculations Step 14: Click on EDITOR to view the output file