AXIS COMPUTATION FOR TRAFFIC ROUTES SUBJECT TO ARBITRARY CONSTRAINTS

ACHSBERECHNUNG FUER VERKEHRSWEGE MIT BELIEBIGEN ZWANGSANGABEN

Graphical design of a road axis layout is carried out by fitting the three basic elements of straight line, circle and transition curve (clothoid) to a freehand line, which then form the basis of the coordinate calculation. This method is used in both traditional and computerised design. Actual practice shows that these solutions for the analytic description of a graphical layout design and the programs based on them are entirely satisfactory for use with electronic computers. The design engineers demand that the graphically determined axis should pass through the fixed points while exactly satisfying the stipulated directional and clearance constraints. The basic mathematical model is derived from the fact that an arbitrary sequence of circles (straight lines) and clothoid segments with continuously varying curvature and direction of the tangent and satisfying two boundary conditions is uniquely defined. This is expressed mathematically by means of a system of 2n-3 non-linear equations, which can be solved iteratively using the developed computer program. The mathematical model is limited to the group of elements "circle-clothoid-clothoid-circle". Nevertheless a layout satisfying all the requirements with respect to the specified constraints can be achieved by suitable adaptation and combination. (TRRL)

• Corporate Authors:

  Ministry of Building and Technology, Austria

  Stuberring 1
  A-1010 Vienna,   Austria 
• Authors:
  • Joscht, W
  • Starkl, L
  • BRAUN, H
  • Harrant, H
• Publication Date: 1979

Language

• German

Media Info

• Features: Figures; Tables;
• Pagination: 76 p.
• Monograph Title: ACHSBERECHNUNG FUER VERKEHRSWEGE MIT BELIEBIGEN ZWANGSANGABEN
• Serial:
  • Strassenforschung
  • Issue Number: 119
  • Publisher: Ministry of Building and Technology, Austria

Subject/Index Terms

• TRT Terms: Axis; Calculation; Circles; Computer programs; Constraints; Curvature; Curves (Geometry); Geometric segments; Graphics; Highway design; Highways; Iterative methods; Layout; Mathematical models; Nonlinear equations; Research reports; Roads; Transition curves
• Uncontrolled Terms: Computation; Straight sections
• Old TRIS Terms: Graphic methods
• ITRD Terms: 6405: Axis; 6423: Circle; 6496: Curve (math); 2870: Degree of curvature; 2755: Highway; 6473: Mathematical model; 8559: Research report; 8645: Software; 2861: Straight (road); 2892: Transition curve
• Subject Areas: Design; Highways; Planning and Forecasting; I10: Economics and Administration; I21: Planning of Transport Infrastructure;

Filing Info

• Accession Number: 00341673
• Record Type: Publication
• Source Agency: Bundesanstalt für Straßenwesen (BASt)
• Report/Paper Numbers: Monograph
• Files: ITRD, TRIS
• Created Date: Dec 22 1981 12:00AM