In order to improve the applicability of back-calculation methods of rigid pavement parameters

this research presents comprehensive analysis of three representative derived indicators of deflection basin for back-calculation of rigid pavement parameters. By systematic analysis and modelling of AREA

intertial point (IP) and Barycentric Horizontal Distance (BHD) method in the ILLI-BACK

the distribution laws of these three methods were investigated quantitatively using numerical analysis

and the nomograph of IP and regression formulas of AREA and BHD were developed respectively to improve the applicability in the practice. Taking typical rigid pavement structure as an example

the accuracy and robustness of three comparative back-calculation methods were verified. Results showed that the back-calculation were greatly simplified using the nomograph and regression formulas. The back-calculation results based on three comparative methods exhibited remarkable difference. BHD significantly improved the accuracy and robustness in back-calculation of rigid pavement parameters by making full use of measurement information at all the sensors and minimizing the fitting error.