PAVEMENT ROUGHNESS AND DEFLECTION STUDIES OF ALABAMA HIGHWAYS

THE ALABAMA HIGHWAY DEPARTMENT ACCUMULATED BENKELMAN BEAM DEFELCTION DATA ON SELECTED BITUMINOUS PAVEMENTS SINCE 1958, AND ROUGHNESS MEASUREMENTS SINCE 1961. FIELD WORK WAS CONDUCTED FOR FIVE YEARS TO OBTAIN PAVEMENT ROUGHNESS AND DEFLECTION DATA TO BE USED AS AN AID IN EVALUATING ROADBED STRUCTURE DESIGN. PAVEMENT SURFACE DEFLECTIONS WERE MEASURED BY BENKELMAN BEAMS. BASED ON THE AVAILABLE DEFLECTION DATA, THE PAVEMENT DESIGNS USED BY THE ALABAMA DEPARTMENT FOR INTERSTATE AND PRIMARY ROUTES APPEAR GENERALLY ADEQUATE. IT IS RECOMMENDED THAT PAVEMENT DEFLECTIONS BE MEASURED AT RANDOM LOCATIONS WITHIN THE PAVEMENT SECTIONS SO THAT STATISTICAL PARAMETERS TO DESCRIBE THE DATA CAN BE USED WITH GREATER CONFIDENCE. THE PAVEMENT ROUGHNESS STUDY WAS CONDUCTED FROM 1960-1964 WITH A BPR ROUGHOMETER. IN JULY 1964 A CHLOE PROFILOMETER WAS OBTAINED. THE AVERAGE ROUGHNESS INDEX FOR NEW BITUMINOUS PAVEMENTS WAS ABOUT 88 INCHES PER MILE. THE AVERAGE INCREASE IN ROUGHNESS INDEX WAS ABOUT 4 INCHES PER MILE PER YEAR. RESURFACING OF THE BITUMINOUS PAVEMENT WITH 150 POUNDS PER SQ. YD. OF BITUMINOUS CONCRETE SIGNIFICANTLY IMPROVED THE ROUGHNESS INDEX OF THE ROUGHER PAVEMENTS. NEW CONCRETE PAVEMENTS IN ALABAMA HAVE AN AVERAGE ROUGHNESS INDEX OF ABOUT 105 INCHES PER MILE. THE PRESENT SERVICEABILITY INDEX OF NEW CONCRETE PAVEMENT IS ABOUT 4.2. THE AVERAGE INCREASE FOR THE PAVEMENTS INCLUDED IN THE STUDY WAS ABOUT 3 INCHES PER MILE PER YEAR. THE RATING SCALE PRESENTLY USED APPEARS TO BE REASONABLE WHEN APPLIED TO BITUMINOUS PAVEMENTS, HOWEVER, THE SAME SCALE APPEARS TO BE SEVERE WHEN APPLIED TO JOINTED CONCRETE PAVEMENTS. THE APPENDICES PRESENT SUMMARY OF DATA FOR EACH PAVEMENT SECTION.

Media Info

  • Pagination: 312 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00207053
  • Record Type: Publication
  • Report/Paper Numbers: HPR 41
  • Files: TRIS, USDOT, STATEDOT
  • Created Date: Jan 5 1970 12:00AM