{"id":3173,"date":"2013-08-25T17:52:32","date_gmt":"2013-08-25T21:52:32","guid":{"rendered":"http:\/\/www.alexblock.net\/?p=3173"},"modified":"2013-12-14T13:41:12","modified_gmt":"2013-12-14T18:41:12","slug":"a-survey-of-selected-elevated-rail-viaducts-part-4","status":"publish","type":"post","link":"https:\/\/www.alexblock.net\/blog\/2013\/08\/25\/a-survey-of-selected-elevated-rail-viaducts-part-4\/","title":{"rendered":"A visual survey of selected elevated rail viaducts: part 4 – monorails, active uses under viaducts, and precast concrete in Puerto Rico"},"content":{"rendered":"

Pulling together some suggestions from the comments of\u00a0the series prologue<\/a>, part 1<\/a>,\u00a0part 2<\/a>, and part 3<\/a>\u2026<\/em><\/p>\n

Monorails:\u00a0<\/strong>Always popular as a technology that can reduce the visual bulk of elevated rail, Alon Levy collected some comparisons showing that purported monorail cost benefits to be mostly illusory<\/a>. But what about visual bulk? Alon makes a note of the smaller required structure:<\/p>\n

It includes a diagram of monorail structures, which can be seen to be quite light and thin. The width of the structure from guideway to guideway is 4.5 meters including both guideway widths, and including the outside appears to raise it to 5.5. Two-track elevated conventional rail structures typically range from 7 to 10.5 meters wide.<\/p><\/blockquote>\n

Mumbai has monorail under construction<\/a>:<\/p>\n

\"Mumbai<\/a>

Mumbai monorail, under construction. CC image from Wiki.<\/p><\/div>\n

One long-standing example is Seattle’s monorail:<\/p>\n

\"Seattle<\/a>

Seattle Monorail, as seen from a neighboring downtown building. CC image from Bala Mainymaran<\/p><\/div>\n

\"Seattle<\/a>

Seattle Monorail from street level. CC image from The West End.<\/p><\/div>\n

New York:\u00a0<\/strong>Commenter Matthew (of\u00a0Walking Bostonian<\/a>)\u00a0offered two photos<\/a>\u00a0from New York of mainline rail infrastructure. The approach for the\u00a0Hell Gate bridge<\/a>\u00a0towers over parts of Queens:<\/p>\n

\"Hell<\/a>

Hell Gate bridge approach. CC image from Matthew in Boston.<\/p><\/div>\n

Another example is from the Long Island Railroad, with retail spaces crammed underneath a viaduct in Flushing, Queens:<\/p>\n

\"LIRR<\/a>

LIRR viaduct, Flushing. CC image from Matthew in Boston.<\/p><\/div>\n

The LIRR shows an example of re-using the space beneath a vaiduct with retail; perhaps without the architectural glamor of the archways in Berlin or Vienna. Nevertheless, it shows the potential for re-using some of the space beneath elevated rail.<\/p>\n

Vienna:\u00a0<\/strong>Neil Flannagan<\/a> (after looking at Berlin examples<\/a>) suggested Vienna<\/a>:<\/p>\n

The Queens Boulevard and Berlin examples really seem like missed opportunities we could have had in Tysons: cheap infill retail using the bridge structure as a roof. It would reduce the barrier effect of the median, focus activity near the stations, and set an example of urban form.<\/p>\n

This was the solution nobody was looking for because we were so set on fighting out the tunnel-versus- overground plan and trying to keep the project afloat. I certainly was guilty of believing that no viaduct could be attractive, and kept arguing for a tunnel. I was looking at the types without considering design. It\u2019s the same trap that NIMBYs do, wanting to minimize the impact by making a building smaller, rather than better. Damn. Looking outside of the box is why Jarrett Walker is so great.<\/p>\n

I would really take a look at Otto Wagner\u2019s\u00a0Wiener Stadtbahn<\/a>. The infrastructure is pretty street-friendly. It\u2019s also very well designed, particularly the\u00a0bridge over the Wienzeile<\/a>.<\/p><\/blockquote>\n

Some images from Vienna:<\/p>\n

\"Vienna<\/a>

Vienna viaduct and bridge structures, with retail spaces beneath. CC image from Wiki.<\/p><\/div>\n

\"Retail<\/a>

Retail beneath a viaduct in Vienna. CC image from Wiki.<\/p><\/div>\n

San Juan, Puerto Rico:\u00a0<\/strong>San Juan’s Tren Urbano was also mentioned in the comments. Google does not have streetview images in San Juan, but a brief Flickr search for CC images turns up the following examples of the system’s elevated structures:<\/p>\n

\"Tren<\/a>

Tren Urbano. CC image from I Am Rob.<\/p><\/div>\n

\"Panorama<\/a>

Panorama of the Torrimar Tren Urbano station. CC image from davsot.<\/p><\/div>\n

 <\/p>\n

\"Tren<\/a>

Tren Urbano. CC image from Paul Sableman.<\/p><\/div>\n

Table of contents:<\/em><\/p>\n