VEHICLE TYPES

194 passengers per train, turns with radii as small as 40m, escalate up/down 6% gradients while reducing the capital costs (by up to 50%) through lighter trains and increased efficiency

- Kuwabara, 2003 p. 140

Monorails are becoming an increasingly popular mode of urban transit, as can be seen by the amount of new projects being undertaken in cities across the world. The technologies involved are well established and have a proven and successful track record.

  

For calculation purposes, data from a readily available monorail technology which would fit the criteria of Malta's requirements was necessary. The data, such as turning radii and hill gradients for monorail trains, passenger carrying capacity, speed and acceleration, etc. helped inform logistical decisions concerning route planning and overall feasibility. Following an analysis and cross-examination of available monorail technologies, the Hitachi Small-type monorail was found to be most suitable. This does not exclude the fact that further research and design could result in a bespoke system better suited to the local scenario, resulting in a more cost-beneficial package.


Straddle-type monorails have proven themselves as the industry standard technology, being implemented in a plethora of projects worldwide. The ideal model would be able to handle tight bends and steep gradients, as is typical of both the Maltese road network and the country's general topography. Monorail trains need to be adequately sized in order to have a reasonable critical ridership rate for feasibility, while being able to transport mass amounts of people with the required efficiency. It is for these reasons, and others, that the Hitachi Small-type monorail was selected. As outlined in New Solution for Urban Traffic: Small-type Monorail System


This reduced-size monorail not only produces lighter systems, but also smaller structural supports, which implies that the visual impact will also be reduced. This further increases the attractiveness of an elevated infrastructure

MONORAIL TECHNOLOGIES

 
 

ALWEG

The ALWEG system is constructed with the beam-on-column and is know for pioneering the straddle-beam monorails. It has been used to construct the Seattle ALWEG monorail with columns set on top of appropriate foundations (cast-in-place, driven pile or spread foundations). Most of the supporting structure consists of T-shaped reinforced concrete columns, averaging at 7.3m high, with 1.2m embedded in the ground. The minimum clearance under the cantilevering cross-arms is 4.6m, and under the rail beams approximately 6m.

 
 

STEEL BOX BEAM

The steel box beam monorail has its beginnings in the early 1960’s in Thun, Switzerland. There the Maschinenfabrik Habegger Company developed small “mini-rails” for fairs and expositions. In conjunction with Von Roll, the first installations were in Lausanne in 1964 and Munich in 1965. The “Habegger-type” monorail, as it is sometimes still referred to, got the most attention at Expo 67 in Montreal, Canada. Von Roll later modified the technology into using a steel box beam. Several other companies now offer this type of monorail for people-mover class systems.

 
 

MAGLEV

Maglev is a relatively modern system which uses an advanced technology in which magnetic forces lift, propel, and guide a vehicle over a guide-way. Therefore, in this system there are no wheels touching the track surface, the train “floats” instead of rolling on the guide-ways.

 
 

INVERTED T SYSTEM

During the 1960’s, a new design for monorail was in prevalent use for small amusement parks and zoos. Developed and sold by Universal Design Limited (UDL), the guide way resembles an inverted T when viewed in a cross section diagram. The vertical element of the guide way are only used for guide wheels, while the lips at the bottom of the track carry the load bearing wheels. While many UDL monorails were installed, no large scale systems made it off the drawing board. One was proposed for the Seattle Monorail, but the Alweg system was selected there. Today several companies are promoting various versions of the inverted T monorail for transit.

 
 

SUSPENDED DOUBLE FLANGE SYSTEM

This system was derived from the system used in factories to transport material from one side of the factory to the other, having small lifting hoists running on rails which were basically I section beams. The system is widely used for everything from butcher shops to commercial laundries to move various items efficiently. The same principle was also applied for public transport monorails. Transit I-Beam monorails would seem to be a logical extension of the industrial monorail. However, the history of this type of monorail has been relegated to amusement centers and fairs. The most famous I-Beam monorail operated for only two years at the New York World’s Fair of 1964-65. Today we know of only one company still active in the promotion of the I-Beam monorail, Titan Global Systems. Their design for a LIM-powered I-Beam monorail has been around for many years, but unfortunately there are no transit I-Beam systems in existence currently.

 
 

CANTILEVERED SYSTEM

Monorails are advertised for many reasons, but narrow guide way is one item at the top of the list. That said there are companies proposing to do better than monorail. Imagine bi-directional travel of transit vehicles on one beam, not two. That is the chief characteristic feature of the mono-beam system. While mono-beam may seem to be a new idea, it has been around for some time. The Scherer Mono-beam was promoted without success in the 1960’s. Still, the concept remains today.

 
 

SUSPENDED SYSTEM (SAFEGE)

The essence of the system was the conversion of the rubber-tired bogie developed for the Paris Metro into a bogie from which the coaches could be suspended to make an aerial railway. The bogie ran inside a hollow box girder on the lower face of which was a slot through which the suspension gear passed. The system enjoyed the same type of quiet, rapid acceleration and braking as did the Metro and the SAFEGE’s ALWEG cousins. The cars were hung on a pendulum type suspension with pneumatic springs, giving stability and comfort even at high speeds. The complete enclosure of the bogies inside the box protected them from the weather, so the system was unaffected by rain, frost or snow. Eurotren Monoviga - http://www.monorails.org/webpix/TPEM5.jpg

 
 

SUSPENDED DOUBLE FLANGE SYSTEM

The first successful use of monorail technology in urban transportation was the Schwebebahn (suspended or floating railway) of Wuppertal, Germany. It has been in operation since 1901. There are two dual-wheeled bogies per car. The double flanged steel wheels run on a single steel rail laid on a girder. Bogies on the original cars had a single motor using a chain to drive both wheels. Current cars use a single motor driving both wheels with worm gears. Reversing at each end of the line is by loop, and a turntable has been installed for short turns. In 1993, between 45,000 and 50,000 people used the Schwebebahn every day. Not bad for a system that’s been around for nearly 100 years.

TECHNOLOGY GAP

Monorails are becoming an increasingly popular mode of urban transit, as can be seen by the amount of new projects being undertaken in cities across the world. The technologies involved are well established and have a proven and successful track record.


The type of monorail system was selected as the authors deemed that its technical specifications satisfy the primary requirements for a monorail system in Malta. This does not exclude the fact that further research and design could result in a bespoke system better suited to the local scenario, resulting in a more cost-beneficial package.