Span Design

Reducing the installed cost of guideways requires minimizing the linear weight while maintaining the highest practical cross section dimentions to increase the strength to materials weight ratio.  This is no different than long span bridge designs that have to carry a hundred times or more the proposed guideway design span load.  Road bridges have no means to prevent two or four lanes of fully loaded semi trucks from stopping on the bridge in a traffic jam.  The guideway vehicles can be programmed to not exceedt the linear load of the designed span strength.  This load would often vary from 50 pounds per linear span foot to 400 pounds per foot at the heaviest.


One or two spaced out heavily loaded vehicles might occupy a low cost gridded access span or short trains of lightly loaded vehicles could use the same span.  Vehicles could break up into pairs or threes and spread out to meetvload requirements then come back together when past a lighter section.


Higher speed fully loaded train capable guideway sections will expierience sag under heavier loads that causes dynamic elastic vibrations or hopping in vehicle suspensions that are harmonically opposed to reducing loads.  Proposed speculatively is active suspensions that might off and on dampen retractions to coincide with entering the stiffer point approaching a pier then give this released energy back after just passing the pier to hop reducing some load on the span center.


Open truss low cross wise structural air resistance is required to reduce running gear and body interference drag, to reduce vulnerability to tornado damage and to reduce sidewise flexing vibrations transfered to the vehicle bodies.


Proposed is a vehicle coupling system the makes a train of vehicles on straighter track sections at very high speeds ridged reducing single vehicle pitch and yaw and sway motions seen in rail cars.  The trains become a long structurally ridged tube under the guideway structural spans.


Proposed is active motorized expansion joints with turnbuckles that are the couplers connecting the spans together.  These motorized joints are also used to set prearch and expand incrementally by having one screw rotation represent the pitch of the rack gears.