BBD, VDF, MSA Analysis
Design Pavement Thickness depending on BBD, VDF & MSA data
Save considerable time for Interpolating values from IRC Charts
This module serves as a complete package for design of flexible Pavement thicknesses. It mainly caters and follows the guidelines as specified in Relevant Indian Road Congress (IRC) Codes. This module can be used as a comprehensive analysis of BBD (Benkelman beam deflection), VDF (Vehicle Damage Factor) and MSA (Million standard axles) and then derive the thickness of design layers like Base, Sub base, structural layers etc... Which may include BC(Bituminous Concrete), DBM(Dense bituminous macadam), BM( Bituminous macadam), WMM(Wet mix macadam), GSB (Granular Sub base), Subgrade , etc..
This module also caters for individual field study requirements like BBD studies alone. The relevant IRC: 81-1997 has been adopted for the analysis. When it comes for a comprehensive solution then other relevant codes like IRC :37-2001 Second revision, IRC: 37-2012 are also adopted along with IRC:81-1997.
1. This module is a one stop solution for BBD, VDF, MSA analysis and generating the final thicknesses of the design layers as per the requirement.
2. It drastically reduces the pain of reading the curves in IRC 81 for Moisture content (%) on X-Axis and Moisture Correction factor on the Y-Axis. It also saves the time considerably and also avoids most of the manual errors which could creep in by reading different figures for different rainfall and soil conditions.
3. It considers all the class of vehicles including tandem axles, tridem axles and multi axles as per the Indian Standards.
PAVEMENT DESIGN –Overlay Design / Reconstruction
Pavement design module of ESurvey Civil Tools helps you to compute the thickness of various Pavement compositions in both Overlay Design Projects and Reconstruction Projects.
In this help, complete procedure is explained in following 5 Topics. Reference : irc.gov.in.037.2012
Creating pavement design file
Calculate Characteristic Deflection by Importing surveyed data
Calculate MSA (Million standard axles) and VDF (Vehicle damage factor) by Importing Traffic survey data and Axle load survey.
Final Computation of pavement layers.
Creating pavement design file
1. Open ESurvey Civil Tools Interface Click on New File menu under File menu
2. Give File name and Save it.
3. Go to Main menu and click on the Pavement Design option
4. Click on Settings button in Pavement design window, Settings window will appear. In Settings, General tab Specify ‘Year of Survey’, ‘Proposed Completion Year’ and ‘Default Traffic Growth or estimated traffic growth’ and Save it.
5. In Homogeneous Section tab, list all section ranges for Overlay and New Construction reaches and Save it. These sections are identified based on the reconnaissance survey and Road Inventory surveys based on the condition of the existing pavement. This survey is done mainly to identify the sections where BBD surveys are to be conducted.
6. In VDF and MSA tab, enter parameter values
a. Lane Distribution Factor
b. Direction Distribution Factor
c. MSA Calculation For
d. Minimum VDF
And Save it.
Calculate Characteristic Deflection by importing survey data
7. Click on BBD button
8. Click on Input button, a BBD input window will open, copy and paste details in all tabs
Temperature, Moisture, Soil Type, Plasticity Index, Rain Fall, Field Book along with Chainage range.
9. Click on Calculate button to calculate Characteristic Deflection. Select the interval or frequency of the lengths as required.
Calculate MSA by Importing traffic survey data
10. Click on MSA/VDF button in pavement design window
11. In VDF Analysis Window - Direction 1 tab and input Vehicle data of Direction 1
12. Before you enter the Direction 1 detail, you can define Vehicle Type by clicking on Codes button. The codes are to be provided in the standard formats based on their axle configuration. Eg, Tandem, tridem etc.. Please refer the IRC code” irc.gov.in.037.2012” for more details
13. Similarly in Direction 2 tab and Input Vehicle data of Direction 2
14. In MSA tab, to Export MSA details, select a Year in the grid and then click on the Export button
15. MSA Report:
16. You can also update Growth Rate of Vehicle in ‘Vehicle Group Growth rate’ window
In Pavement Design window, either enter all the survey details by clicking on BBD, MSA / VDF button or Enable Check box ‘Manual Characteristic Deflection’, ‘Manual MSA Value’ and enter their project specific values manually. Select Homogeneous Section for which you want to find final results. Click on Calculate button in an Overlay Design group or Reconstruction group and compute the final result. The results of the pavement layer thicknesses are displayed as per IRC. Equivalence factors are not included in the package and are given in terms of BM for structural layers.
Click Export button on the screen to Export the values to Excel.