Trams have been used since the 19th century, and since then, there have been various uses and designs for trams around the world. This article covers the many design types, most notably the articulated, double-decker, drop-centre, low-floor, single ended, double-ended, rubber -tired, and tram-train; and the various uses of trams, both historical and current, most notably cargo trams, a dog car, hearse tram, maintenance trams, a mobile library service, a nursery tram, a restaurant tram, a tourist tram, and as mobile offices.
Types of Tram Designs
Articulated
Articulated trams, invented and first used by the Boston Elevated Railway in 1912–13 at a total length of about twelve meters long (40 ft) for each pioneering example of twin-section articulated tram car, have two or more body sections, connected by flexible joints and a round platform at their pivoting midsection(s). Like articulated buses, they have increased passenger capacity. In practice, these trams can be up to long (such as CAF Urbos 3 in Budapest, Hungary), while a regular tram must be much shorter. With this type, the articulation is suspended between carbody sections.
In the Škoda ForCity, which is the world's first 100% low floor tram with pivoting bogies, a Jacobs bogie supports the articulation between the two or more carbody sections. An articulated tram may be low-floor variety or high-floor (regular) variety. Newer model trams may be up to long and carry 510 passengers at a comfortable . At crush loadings this would be even higher.
Double Decker
A double-decker tram is a tram that has two levels. Some double-decker trams have open tops. The earliest double-deck trams were horse drawn. The first electric double-deck trams were those built for the Blackpool Tramway in 1885, one of which survives at the National Tramway Museum.
Double decker trams were commonplace in Great Britain and Dublin in Ireland before most tramways were torn up in the 1950s and 1960s. New York City's New York Railways experimented in 1912 with a Brill double deck Hedley-Doyle stepless centre entrance car, nicknamed the "Broadway Battleship", a term that spread to other large streetcars. Hobart, Tasmania, Australia made extensive use of double decker trams. The most unusual double-decker tram used to run between the isolated Western Australian outback town of Leonora and the nearby settlement of Gwalia.
Double decker trams still operate in Alexandria, Blackpool, Hong Kong, Dubai and Oranjestad.
Drop-Centre (lowered central section) Many early 20th century trams used a lowered central section between the bogies (trucks). This made passenger access easier, reducing the number of steps required to reach the inside of the vehicle. These cars were frequently referred to as "drop-centres". It is believed that the design first originated in Christchurch, New Zealand, in 1906 when Boon & Co Ltd. built twenty-six such trams in three series. A number of these trams have been preserved. They were a favored design in Australia and New Zealand, with at least 780 such tramcars being built for use in Melbourne alone. Trams built since the 1970s have had conventional high or low floors.
Low floor
From around the 1990s, light rail vehicles not made for the occasional high platform light rail system have usually been of partial or fully low-floor design, with the floor above top of rail, a capability not found in older vehicles. This allows them to load passengers, including those in wheelchairs or with perambulators directly from low-rise platforms that are not much more than raised footpaths/sidewalks. This satisfies requirements to provide access to disabled passengers without using expensive wheelchair lifts, while at the same time making boarding faster and easier for other passengers. Passengers appreciate the ease of boarding and alighting from low-floor trams and moving about inside one hundred per cent low-floor trams. Passenger satisfaction with low-floor trams is high. In some jurisdictions this has even been made mandatory since the 1990s, for example by Her Majesty's Railway Inspectorate in Britain and the Disability Discrimination Act in the United Kingdom and other Commonwealth countries.
Various companies have developed low-floor designs, varying from part-low-floor (with internal steps between the low-floor section and the high-floor sections over the bogies), e.g. Citytram and Siemens S70, to one hundred per cent low-floor, where the floor passes through a corridor between the drive wheels, thus maintaining a constant (stepless) level from end to end of the tram.