VISUAL QUALITY STUDIES IN HIGHWAY DESIGN

A HIGHWAY DESIGN COMPUTER PROGRAM IS DESCRIBED, TE.GI (IMPOSED GEOMETRY AUTOMATIC ALIGNMENT CALCULATIONS), WHICH CARRIES OUT ALL NUMERICAL CALCULATIONS FOR A PROJECT, AND PRODUCES A FULL SET OF DRAWINGS INCLUDING ACCURATE PRESPECTIVE VIEWS. THE PROGRAM USES AN ORIGINAL REPRESENTATION OF THE GROUND, THE NUMERICAL GROUND IMAGE, WHICH ALLOWS THE INTERPOLATION OF ANY GROUND LEVEL WITHIN THE DEFINED ZONE TO A PRECISION OF ABOUT 5 IN. , AT A RATE OF 900 POINTS INTERPOLATED PER MINUTE. THE NECESSARY INTERPOLATION PROGRAMS FORM PART OF A PROGRAM PACKAGE COMPOSED OF SEVEN SECTIONS, TREATING THE VARIOUS DESIGN ASPECTS, WITH AUTOMATIC DATA TRANSFER BETWEEN SECTIONS. THE PACKAGE CAN BE USED SECTION BY SECTION TO KEEP PACE WITH DESIGN PHASES, AND IS WELL ADAPTED TO THE STUDY OF SEVERAL DIFFERENT ALTERNATIVES. PARTICULAR EMPHASIS IS PLACED ON THE USE OF THE PERSPECTIVE DRAWINGS TO CORRECT FAULTY DESIGNS. THE MOST COMMON ERRORS ARE ILLUSTRATED, WITH COMMENTS ON HOW CORRECTIONS COULD HAVE BEEN MADE. BEFORE AND AFTER EXAMPLES ARE GIVEN FOR AN ACCESS POINT WHERE THE DESIGN WAS CHANGED WHEN PERSPECTIVE DRAWINGS SHOWED THAT THE NEW DESIGN WOULD BE INHERENTLY LESS LIKELY TO CAUSE ACCIDENTS. THE USE OF THE PROGRAM TO OBTAIN THE PERSPECTIVE VIEWS IS EXPLAINED, AND THE AVAILABLE TYPES OF VIEW ARE GIVEN WITH THEIR APPROXIMATE COSTS. AN INDEPENDENT PROGRAM BASED ON THE PERSPECTIVES PHASE OF THE TE.GI PACKAGE IS ALSO EXPLAINED, ALONG WITH ITS USE FOR STUDYING INTERCHANGES AND OTHER ASPECTS OF DESIGN THAT CANNOT BE HANDLED DIRECTLY BY TE.GI. BOTH OF THESE PROGRAMS CAN BE USED TO OBTAIN A LARGE NUMBER OF CLOSELY PERSPECTIVE DRAWINGS THAT CAN BE PHOTOGRAPHED USING CARTOON FILM TECHNIQUES TO OBTAIN ANIMATED VIEWS OF THE PROJECT AS SEEN BY A DRIVER FOLLOWING ANY TRAJECTORY AT ANY SPEED. THE COST OF THESE CARTOON FILMS WILL BE REDUCED BY MODIFICATIONS TO THE PROGRAM, ADAPTING IT TO NEW EQUIPMENT COMING ONTO THE MARKET, SUCH AS A SMALL HIGH-PERFORMANCE COMPUTER COUPLED TO A CATHODE-RAY TUBE AND AN AUTOMATIC CAMERA. /AUTHOR/

Media Info

  • Media Type: Print
  • Features: Figures; References;
  • Pagination: pp 46-57
  • Monograph Title: Geometric design: photogrammetry and aerial surveys
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00203357
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Oct 14 1994 12:00AM