HigherwaylogoHigherway Guideway

The guideway is often the most expensive part of the initial cost for a transit system. The Higherway guideway has several features to keep the life cycle cost as low as possible:

  • Low cost manufacturing of tracks with automated roll-forming and curve bending machines to shape sheet steel. This is similar to the materials and manufacturing methods used to make highway guard rails.
  • Support arms stamped in factory
  • Support poles like traffic signal supports.
  • Simple design for electrical power can be assembled easily and taken apart for maintenance. The aluminum/stainless steel high-voltage power/guidebar is insulated and clamped between the two halves of the upper part of the track.
  • Suspended vehicle design provides for a safe , clean, running surface, and reduced stress on the guideway when vehicles lean in curves and cross-winds.

  • Different support techniques will be used in different locations. An example for an urban one-way guideway is shown on the left below. The track on the left is for accelerating vehicles, the track on the right has a line speed of 45 meters per second (100 mph) except on steep hills and curves. A rural two-way guideway is on the right below. The Pelican on the left is coming toward you, the Dove on the right is going away from you. It uses smaller support poles and more of them to reduce foundation and structure costs. Because it is farther from stops it doesn't need acceleration tracks.

    1-way urban arterialRural 2-way two-track guideway

    Track

    The track is made of roll-formed and corrosion-protected steel. See cross-section drawing.

    Higherway Track
CrossSection Track side view

    This drawing is for spans up to 24 m. Longer spans will be taller or have additional structures supporting the tracks. Some other drawings on this website show an older design for short spans (ramp tracks) and without the utility duct. Not shown in the cross section drawing are holes in the upper part of the track to reduce loads from cross winds, the junctions between track sections, and stiffeners which may be needed periodically to prevent deflection of the track.

    Special track sections

    The Higherway track goes over and around the bogie part of the vehicles. This is advantageous for quick vehicle switching and to provide a clean, dry running surface for the tires. However, since it is a high-speed (up to 45 m/s) suspended system in merge/diverge Y-sections one side of the tires will not be supported and means must be provided to keep the bogies from falling through the gap in the bottom of the track. Higherway guideways will have more Y-sections than most other systems because there will almost always be acceleration tracks next to the high-speed tracks to enable merging without slowing the vehicles on the main high-speed tracks.

    Requirements on the track and bogie for going through merge/diverge Y-sections of track:

    1. The bogies must not overturn and fall through the track. a. stabilizer wheels on the bogie must be engaged and locked in place by the bogie and track before the bogie enters the Y-section. b. the bogie must interact with the track before a diverge Y-section to force the bogie mechanical switch to either the left or right position. c. the track must force the bogie stabilizer wheels to run on the outside edge of the track and lock in place before a merge Y-section.

    2. There will be at least four track cross-sections:

    3. The track/bogie interactions have to work correctly to allow the bogies to navigate and not overturn and fall through the track if the bogies are going backwards. (They go backwards to exit dead-end spurs and to clear the track in case of line blockage.) Approaching a diverge Y the track would go from a to d to c to b to a. Approaching a merge Y the track would go from a to b to c to d to a. The drawings above illustrate the added complexity and precision required for track sections b, c, and d. Section c is the most critical because it is where there is the possibility of merge collisions and bogies falling to the ground. We expect careful design of shock absorbers in the track (not shown in drawing) and thorough development testing to reduce this hazard to a negligible level.

    Different support structure is needed for Y sections in urban areas to allow the vehicles to cross over between acceleration tracks and through tracks without hitting the support poles. An example is in the drawing below.

    Urban Y-section needs an
extra cross arm

     The current plan for the manufacturing process is:

      1.  Unroll the sheet steel
      2.  Punch holes for mounting bolts, sensors, etc.
      3.  Shear the end
      4.  Roll form the shape
      5.  Transfer to hydraulic bending machine
      6.  Use information from computer aided design program to bend track if a curve is needed
      7.  Transfer to chemical processing tanks - cleaning, plating, painting
      8.  Dry, bake if needed for paint
      9.  Add location markers/identifiers (bar codes, radio identification transponders, magnets)
      10.  Cut powerbar to length
      11.  Bend powerbar if needed to match track section
      12.  Attach connector pieces to ends of powerbars and attach insulator
      13.  Bolt together track sections from four roll-formed steel pieces and insulated powerbar
      14.  Attach some of the stiffeners to the outside of the track
      15.  Load on semi-trailer for delivery to guideway construction site.

    In some locations stainless steel will be the most economical choice for the track material. For stainless, steps 7 and 8 above may be omitted unless painting is still required for aesthetic reasons.

    Bridges

    Higherway guideways can be added to many existing bridges at relatively low cost because:

  • They are small and light enough that the basic bridge support structure won't have to be reinforced.
  • On cable suspension bridges the guideway can be supported above the roadway by attaching the cross arms to the cables.
  • On reinforced concrete bridges the guideway vertical support poles can be attached to bolts cemented in holes bored into the concrete.

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    This page last updated June 1, 2003