PASSENGER CAR OVERHANG AND UNDERCLEARANCE AS RELATED TO DRIVEWAY PROFILE DESIGN. II. STREET AND HIGHWAY DESIGN

THE AUTOMOBILE INDUSTRY HAS BEEN CHANGING THEIR DESIGN OF CARS BY MAKING THEM LONGER AND LOWER. ON MOST MAKES OF CARS THE UNDERCLEARANCE HAS BEEN REDUCED AND BOTH THE WHEEL BASE AND OVER-ALL LENGTH HAVE BEEN INCREASED TO SUCH AN EXTENT, THAT SUFFICIENT UNDERCLEARENCE IS NOT BEING PROVIDED. THE PROBLEM OF INSUFFICIENT UNDERCLEARANCE OF CARS ENTERING OR LEAVING DRIVEWAY ENTRANCES IS EXAMINED IN CINCINNATI. CONSTRUCTION METHODS FOR CONNECTING DRIVEWAYS TO NEW HIGHWAY IMPROVEMENTS ARE DESCRIBED. IN 1942, THE CINCINNATI CURB STANDARD HAD A BATTERED VERTICLE FACE AND A DEPTH OF 6-1/2 IN. FROM GUTTER TO TOP OF CURB. THIS CURB PROFILE CREATED BUMPER SCRAPING PROBLEMS IN 1951. A NEW STANDARD DRIVEWAY DESIGN DECREASING THE CURB DEPTH FROM 6-1/2 IN. TO 5-1/2 IN. ACROSS THE DRIVEWAY AND SAGS THE WALKGRADE A CORRESPONDING 1 INCH. THE FOLLOWING PROCEDURE IS RECOMMENDED FOR PROPER HIGHWAY DESIGN: (1) DESIGN THE DRIVEWAY PROFILE AS NEARLY AS POSSIBLE TO AVAILABLE STANDARDS, (2) PLOT THE PROFILE IN A NATURAL ( 2 FT TO 1 IN.) SCALE, (3) PREPARE A CUTOUT MODEL CAR ON THE SAME SCALE AS THE PROFILE, AND (4) SLIDE THE CUTOUT MODEL ALONG THE PROFILE FOR FINDING ANY TROUBLE SPOTS AND ADJUST THE PROFILE WHERE NECESSARY.

Media Info

  • Monograph Title: Relation between vehicle characteristics and highway design
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00203349
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Aug 19 1994 12:00AM