عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Evaluation of existing flexible pavement condition at network level requires structural assessment which is performed by FWD device using effective structural number (SNeff) parameter. Deflection data analysis requires layer thicknesses known which must be measured by GPR device or core drilling and pit boring. The AASHTO 93 selected as a base method, so FWD deflection data and layer thicknesses measured by GPR were converted to effective structural number. To reduce the cost and time consumption at network level assessment, layers thickness have been removed and a non-linear regression model was developed based on 3000 deflection basin parameters to determine effective structural number. Then the deflection basin parameters were studied and their correlation with SNeff determined using SPSS software. The analysis showed stronger relationship between AUPP, SCI and dimensionless parameters normalized by central deflection with SNeff. Thus a non-linear regression model obtained involving SCI, AUPP and D90/D0 with 0.9 determination coefficients. The developed model with 0.9 determination coefficients has considerable superiority in comparison with Jameson model with 0.84 determination coefficient which is previously presented.