Grand union
A grand union is a rail track junction where two double-track railway lines cross at grade, often in a street intersection or crossroads. A total of sixteen railroad switches (sets of points) allow streetcars (or in more rare installations, trains) coming from any direction to take any of the three other directions. The same effect maybe achieved with two consequent wyes if the location allows for space.
Complexity
These types of complex junction are expensive to build and expensive to maintain. Special parts, sometimes made of manganese steel, are needed for each location where one rail crossed another (a "frog"); these parts often need to be custom-made and fitted for each single location, depending on the specific angle of crossing of the intersecting streets.
A full grand union junction consists of 88 frogs (where one rail crosses another rail), and 32 switchpoints (point blades) if single-point switches are not used. A tram or train crossing the junction will encounter between four and twenty frogs within the space of crossing the junction.
For all of the possible tracks of a grand union to be used during normal operation, at least six different tram routes have to cross the union. In an intersection with lines oriented towards cardinal directions, these could be: north-south, north-east, north-west, south-east, south-west, and east-west.
Three-Quarter, Half, and Butterfly Unions
Three-quarter unions are similar to grand unions in that they are also rail track junctions where two double-track railway lines cross at grade, often in a street intersection or crossroads; the primary difference being that one corner of the crossing does not have curved junction tracks, with the union having a total of twelve railroad switches (sets of points).
Half unions are similar, but only have curved junction tracks on two adjoining corners of the intersection, with a total of eight switches/points.
Butterfly unions share the total of eight switches/points, but the curved junction tracks are on opposing corners.
Examples
- Toronto, Ontario, Canada: The most extensive street railway system in North America is the Toronto streetcar system of the Toronto Transit Commission in southern Ontario, which has 19 four-way streetcar intersections, including four grand unions, five three-quarter unions, four half unions, and four butterfly unions (Some of which have additional connections that do not fit typical classifications); as well as a number of other (nonstandard) union types. The "traditional" Grand Unions are located at Bathurst and King (43°38'38.14"N 79°24'9.50"W); Spadina and King (43°38'43.73"N 79°23'42.09"W) and Spadina and Queen (43°38'55.43"N 79°23'46.91"W)[6]
- Milan, Italy: the Milan tram network has two grand unions. The first is a nonstandard design located at piazza 24 Maggio,[7] and the second located nearby at piazzale Porta Lodovica.[8]
- Amsterdam, Netherlands: As of 2009[update], the Amsterdam tram system continues to have four grand unions. However, none of them has tram routes running in all directions under normal operation. They are located at 52°21'17.39"N 4°54'4.49"E;[9] 52°21'9.99"N 4°53'28.04"E;[10] 52°21'45.91"N 4°52'31.04"E[11] and 52°22'12.13"N 4°51'0.94"E.[12][13]
- Kazan, Russia: Kazan Tram system has one grand union. It is located at 55.780459 N, 49.112853 E[15].
- Moscow, Russia: Moscow Tram system has one three-quarter union on Preobrazhenskaya Ploshad [16]
- Philadelphia, Pennsylvania, USA: SEPTA has a surviving example of a half union located at the intersection of Chester Avenue and 49th Street;[18][19] and PTC previously had two butterfly unions, the first at Erie Ave and Old York Road[20] and the second at Lancaster Avenue and 33rd Street;[21] as well as a second half union at Allegheny and 22nd Street.[22]
- Rochester, New York State, USA: Rochester's surface streetcar system had three full grand unions, all of which were located on Main Street, as well as two three-quarter unions, and three half unions.[23][24]
- Kraków, Poland The system has three full Grand Unions, one at 50° 3'27.42"N 19°57'32.40"E one at 50° 3'23.40"N 19°56'43.63"E and one at 50° 4'46.65"N 20° 1'38.49"E. There is a "Grand Circle" at Centralny Square, 50° 4'19.56"N 20° 2'14.46"E, the "Grand Circle" which has the same route function as a grand union and also provides a loop for all lines. There is a 3/4 Grand Union at 50° 3'6.26"N 19°56'30.22"E and a 5/8 Grand Union at 50° 4'24.31"N 20° 1'2.89"E.
- Poznan, Poland: The Poznan Tram system has 6 grand unions, which may be the most extant in any city. They are located at: 52°24'37.94"N, 16°54'48.53"E;[25] 52°24'28.02"N, 16°54'44.97"E;[26] 52°24'9.54"N, 16°53'20.65"E;[27] 52°23'24.39"N, 16°53'39.07"E;[28] 52°22'48.68"N, 16°56'35.21"E[29] and 52°23'57.53"N, 16°57'8.97"E.[30] All can be seen in detail on Google Earth.
- Warsaw, Poland: The Warsaw system has two grand unions, first at 52°14'30.79"N 20°59'37.00"E[31] and second at 52°14'13.30"N 20°58'48.62"E.[32] There is a 3/4 union at 52°15'17.24"N 20°58'57.11"E.[33]
- Munich, Germany: While not a traditional Grand Union, the Munich tram system has a "Grand Circle" which has the same route function as a grand union and also provides a loop for all lines, it is located a Maximilian Square, 48° 8'15.27"N, 11°35'17.02"E.[34]
- Karlsruhe, Germany: The Karlsruhe system has a single grand union located at 49° 0'8.96"N 8°23'39.77"E.[35]
- Kassel, Germany: The Kassel system has a single grand union located at 51°19'4.87"N 9°30'1.02"E.[36]
- Basle, Switzerland The Basle system has a single (nonstandard) grand union located at 47°33'4.83"N 7°35'41.89"E.[37]
- Cottbus, Germany Has at least one Grand Union at 51°45'39.86"N 14°19'51.39"E. There appears to be a 3/4 Grand Union at 51°44'57.54"N 14°19'42.50"E however the Google Earth image lacks the resolution to confirm all routes.
- Dresden, Germany Has a Grand Union at 51° 3'49.55"N 51° 3'49.55"N; a 5/8 Grand Union at 51° 3'47.55"N 13°44'13.53"E there is only a single connection on the north route, and a Butterfly Union at 51° 2'58.09"N 13°44'39.27"E
- Duisberg, Germany has a Butterfly Union at 51°30'7.44"N 6°45'25.78"E
- Leipzig, Germany has a Grand Union at 51°20'39.35"N 12°22'15.99"E it is unique in interfacing with four tracks at Goerdelerring tram stop. There is a 3/4 Grand Union at 51°19'56.49"N 12°20'19.68"E a half Grand Union at 51°20'31.31"N 12°21'31.15"E and Butterfly Unions at 51°19'12.95"N 12°19'48.80"E, 51°20'20.36"N 12°21'44.96"E and 51°21'44.93"N 12°21'55.79".
- Granz, Austria has a Grand Union at Jakominiplatz, 47° 4'1.45"N 15°26'30.92"E
See also
References
- ^ Victorian Heritage Database: photographs and diagram of junction
- ^ [1] Google Maps: 217 Balaclava Rd, Caulfield North VIC 3161, Australia
- ^ Edmonton Radial Railway 1924 track map
- ^ Edmonton Radial Railway Society photograph, 109th St. and Jasper Ave., 1904
- ^ Musée McCord Museum photograph - Tramway crossing under construction, 1893
- ^ http://transit.toronto.on.ca/archives/maps/cars06.pdf
- ^ [2] Google Maps: Piazza 24 Maggio, Milano Italy
- ^ [3] Google Maps: Piazzale Porta Lododica, Milano Italy
- ^ [4] Google Maps: Van Woustraat 83III 1074 Amsterdam, The Netherlands
- ^ [5] Google Maps: Ceintuurbaan 55-157 1072 Amsterdam, The Netherlands
- ^ [6] Google Maps: Eerste Constantijn Huygensstraat 98 1054 Amsterdam, The Netherlands
- ^ [7] Google Maps: Jan Evertsenstraat 144II 1056 Amsterdam, The Netherlands
- ^ see Sporenplan.nl
- ^ Graham Stewart, The End of the Penny Section: When Trams Ruled the Streets of New Zealand, rev ed. (Wellington: Grantham House, 1993), p. 149.
- ^ [8] Google Maps: 55.780459 N, 49.112853 E
- ^ [9] Google Maps: Preobrazhenskaya Ploshad, Moscow Russia
- ^ www.Chicago-L.org Photo "tower18l.jpg" taken June 19, 2006.(Retrieved November 2009)
- ^ Original PRT specialwork drawing sheet 10, chart 48.
- ^ PTC Track Map detail, 1954, bottom right corner of image
- ^ Original PRT specialwork drawing sheet 16, chart 66.
- ^ PTC Track Map detail, 1954, center left of image
- ^ PTC Track Map detail, 1954, center left of image
- ^ Map of Rochester Subway, see inset section for surface track layout
- ^ Powers Building photograph, Rochester NY, 1904
- ^ [10] Google Maps: Franklina Roosevelta 11, Poznań, Poland
- ^ [11] Google Maps: Rondo Kaponiera, Poznań, Poland
- ^ [12] Google Maps: Rondo Jana Nowaka-Jeziorańskiego, Poznań, Poland
- ^ [13] Google Maps: Hetmańska 57, Poznań, Poland
- ^ [14] Google Maps: E261 Poznań, Poland
- ^ [15] Google Maps: E261 Poznań, Poland
- ^ [16] Google Maps: 629 Warszawa, Poland
- ^ [17] Google Maps: Rondo Kercelak, Warszawa, Poland
- ^ [18] Google Maps: Rondo Zgrupowania AK "Radosław", Warszawa, Poland
- ^ [19] Google Maps: Maximilianstraße 47 80538 München, Germany
- ^ [20] Google Maps: Karlstraße 63 76137 Karlsruhe, Germany
- ^ [21] Google Maps: Untere Königsstraße 60 34117 Kassel, Germany
- ^ [22] Google Maps: Aeschenplatz 1 4052 Basel, Switzerland
- ^ [23] Google Maps: Zenklova 180 00 Praha 8, Česká republika
- ^ [24] Google Maps: Strossmayerovo náměstí 976/1 170 00 Praha 7-Holešovice, Czech Republic
- ^ [25] Google Maps: Palackého 621/1 779 00 Olomouc, Czech Republic
- ^ [26] Google Maps: Jugoslávská 18 613 00 Brno-sever, Czech Republic
