Tramways and Light Rail Transit (LRT) offer convenient, efficient and environmentally friendly transportation through our city streets. Reducing congestion and improving air quality, they bring huge benefits to the urban environment.
Most modern light rail and tramway networks comprise both street running and segregated route areas, often requiring differing rail types from our extensive product range. To negotiate the twists and turns of our cityscape, routes typically negotiate tight curves and steep gradients.
This challenging environment combined with high traffic frequency and short distances between stopping points accelerate the issues of rail wear and corrugation.
Typical issues experienced by light railways include the need to minimise life-cycle costs while reducing environmental impacts such as vibration and corrosion.
Solving Traffic congestion?
One line of light rail (requires 7.6 m, 25′ right of way) has a theoretical capacity of up to 8 times more than one 3.7 m (12 foot) lane on a freeway, excluding busses, during peak times. Roads have ultimate capacity limits that can be determined by traffic engineering, and usually experience a chaotic breakdown inflow and a dramatic drop in speed (a traffic jam) if they exceed about 2,000 vehicles per hour per lane (each car roughly two seconds behind another).
Since most people who drive to work or on business trips do so alone, studies show that the average car occupancy on many roads carrying commuters is only about 1.5 people per car during the high-demand rush hour periods of the day. This combination of factors limits roads carrying only automobile commuters to a maximum observed capacity of about 3,000 passengers per hour per lane. The problem can be mitigated by introducing high-occupancy vehicle (HOV) lanes and ride-sharing programs, but in most cases, policymakers have chosen to add more lanes to the roads, despite the knowledge that this will only increase congestion.
By contrast, light rail vehicles can travel in multi-car trains carrying a theoretical ridership up to 20,000 passengers per hour in much narrower rights-of-way, not much more than two car lanes wide for a double track system. They can often be run through existing city streets and parks, or placed in the medians of roads. If run in streets, trains are usually limited by city block lengths to about four 180-passenger vehicles (720 passengers). Operating on two-minute headways using traffic signal progression, a well-designed two-track system can handle up to 30 trains per hour per track, achieving peak rates of over 20,000 passengers per hour in each direction. More advanced systems with separate rights-of-way using moving block signaling can exceed 25,000 passengers per hour per track.
|Car||Car + bus||Car + light rail|
|Source: Edson & Tennyson, 2003]|