APPLICATIONS OF A GENERAL CURVE FITTING PROCEDURE TO AASHO ROAD TEST DATA

IN MOST CASES, THE MATHEMATICAL MODELS USED FOR FITTING AASHO ROAD TEST DATA WERE NOT LINEAR IN THE COEFFICIENTS TO BE DETERMINED BY THE ANALYSIS. BECAUSE ONLY LEAST SQUARES LINEAR REGRESSION ANALYSIS WAS AVAILABLE AT THE ROAD TEST, THE SUMMARY EQUATIONS THAT WERE DEVELOPED AND REPORTED WERE DERIVED BY A SERIES OF LINEARIZATIONS OF THE NONLINEAR MODELS. AS A RESULT, THE COEFFICIENTS THAT WERE OBTAINED WERE NOT NECESSARILY OPTIMUM WITH RESPECT TO ANY PARTICULAR CRITERIA FOR THE RESIDUALS FROM THE EQUATIONS. THIS PAPER DESCRIBES THE APPLICATION TO ROAD TEST DATA OF A GENERAL CURVE-FITTING PROCEDURE THAT HAS BEEN PROGRAMED FOR THE BENDIX G-15 D COMPUTER. THE NEW PROCEDURE CAN BE USED FOR LINEAR OR NONLINEAR MODELS AND WITH ANY DESIRED RESIDUAL CRITERION; E.G., LEAST SQUARED AND MINIMUM ABSOLUTE RESIDUALS. RESULTS ARE GIVEN FOR APPLICATIONS OF THE NEW PROCEDURE TO THE DERIVATION OF PRESENT SERVICEABILITY INDEX FORMULAS AND PAVEMENT PERFORMANCE EQUATIONS. ALTHOUGH THE NEW RESULTS REFLECT ONLY SMALL DIFFERENCES FROM THE CORRESPONDING RESULTS GIVEN IN HRB SPECIAL REPORT 61E, THE FIT HAS BEEN IMPROVED THROUGH THE REDUCTION OF CERTAIN BIASES THAT WERE INHERENT IN THE PREVIOUS METHODS OF ANALYSIS. THE PAPER ALSO PRESENTS RESULTS OBTAINED WHEN ROAD TEST PERFORMANCE DATA ARE SUMMARIZED WITH MODELS THAT ARE SIMPLER IN FORM YET MORE COMPREHENSIVE THAN THOSE EMPLOYED IN PREVIOUS ROAD TEST REPORTS.

Media Info

  • Media Type: Print
  • Features: Appendices; Figures; References; Tables;
  • Pagination: pp 1-25
  • Monograph Title: Extension of AASHO road test concepts
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00206201
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Dec 12 1994 12:00AM