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| Sign in a New York City medical building: "Mental Health Prevention Center". |
et's take a look at the supports that are needed to carry the beams. As most of the beams in a typical application would be constructed out in the open, most of these supports will consequently be poles, planted in the ground. But one could always take advantage of surrounding features (such as buildings and cliffs) to help carry the beams. Also, in narrow streets, there might not be sufficient space to erect poles, in which case adjoining buildings would have to be used to anchor the beam supports.This is not a technical page, just an overview of technique and options available. |
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he open-air poles should be designed so that they can easily be transformed from one-way to two-way
traffic (and back), as shown in figures 1 and 2. The length of the horizontal arm on the top of the pole has to be designed not only for the widest
cars that are to be trafficking the route, but also to take account the swinging motions
that can arise as a consequence of speeding through curves (slightly exaggerated in figure 3).
| Many poles will serve as conduits for the electrical power needed by the beam-carried cars (as indicated in figure 2).They could also serve as lighting poles. Some poles should be equipped with computer terminals for the passengers. These will serve both as information screens and as a means to call a car to the place where the passenger is waiting, something like a taxi service. |  |
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7 factors will decide the height of the poles:
| "The Swan neck pole" (figure 4) can be a necessary design in places where the ground is unstable. The entire pole will have to be replaced with the pole in fig. 2 if there is a conversion to double-beam traffic. Where the ground is very unstable and solid rock is too far below to be conveniently reached, this pole will have to be modified, as shown in figures 5 and 6, so that the ground support will come vertically under the load. With a reinforced foundation according to fig. 6, the Swan-neck pole might not be necessary. |
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How far in between must the beam supports be placed? We need to consider: | The narrower, vertical section of the pole should be designed so that it can easily be attached on top of an existing pole. This requirement makes it possible, later on, to increase the height of the pole, to carry more beams, such as for an intersection as is shown in fig. 9. The distance of the poles from each other depends on the beam dimensions and on the ground conditions. In the case of SIPEM (i.e. the existing site in Dortmund, Germany), the distance between poles is between 25 and 35 meters. At such distances, the poles would not be more noticeable than ordinary lamp-posts along streets. The width of the poles (i.e. the broadness of the track) is accomodated to suit the broadest of the vehicles that are to use the beams (fig. 9 illustrates poles for cars with 3 seats beside each other, whereas the pole in fig. 8 can handle 4-seat cars).  |
 Narrow passages could have poles that are not of the widest sort, and consequently could not handle the broadest cars. As earlier stated, one also has to take into account the sideways swinging motions that will be caused by the centrifugal force, as the cars move through a curve (fig. 3). |
What is meant be "near-ground traffic" (point 7 above)? Well, one could imagine places such as narrow city streets, etc. where beams up high would block the sunlight or for other reasons would be unsuitable. Low-level beams (figure 10) could then be a practical solution.
The beamcars would behave almost like streetcars. They would travel about 10 - 30 centimeters above the ground, and they dock at stations by either of 3 practical solutions: |
 Figure 11
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uilding beam networks in eartquake-prone areas means that one has to take precautions in the beams themselves for the fact that the poles might move. Such precautions include movable joints between the beam segments so that the structure (hopefully) won't break apart during the quake, and detectors that signal after the quake that some poles have moved. But what could be done to the poles themselves? Well, they could conceivably be equipped with computer-controlled hydraulic arms that would compensate for dislocations by moving the upper parts of the poles so as to keep the beams straight. But, since the poles are relatively easily mounted and dismounted, |
 Figure 12the best would probably be to temporarily shut down traffic on dislocated beams after the quake, put temporary supports under them, remove the poles, make new foundations for them, and put the poles back up again. This could be done in a couple of days. But, realistically speaking, work crews would probably be occupied with more urgent matters after an earthquake, so, for that reason, beamtraffic would probably be suspended as much as other kinds of traffic after a severe quake. |
mergency braking of the beamcars might be necessary, if something out-of-the-ordinary should occur. Accelerating and decellerating beamcars always transfer some force to the beams according to the law of opposite forces. What we are talking about here is the so-called longitudinal force (A in figure 14), that applies itself along the beams, in the direction of travel. This force is transferred to the ground by way of the supporting poles (from B to C in the figure), and, in so doing, excerts a sideways strain on the poles, trying to make them tip over.In an emergency braking-situation, the force that is thus transferrad is where F is the force (in Newton), m is the mass of the vehicle (measured in kilogram; both of the cabin and of the propulsion vehicle inside the beam) and a is the decelleration (in m/s2). |
 Figure 14
Thus, if the vehicle weights 1.000 kg and the decelleration is 3g (where g is the earth´s gravity at sealevel and 45 degrees latitude, i.e. 9.81 m/s2, i.e. almost 10 m/s2), the force on the beams become This force is unevenly distributed among the poles. Generally, the poles that are closest to the braking beamcar would have to take on most of it. Another consideration is that the higher up from the ground the beam is, the more strain this force would put on the pole´s foundation. As this distance increases (D in the figure), the moment of the force becomes larger, and the pole´s foundation must consequently be sturdier. |
| A separate category of poles are those that are mounted in pairs, in order to carry more than 2 parallell beams at the same altitude, as illustrated in figure 16. They could also be used for beam traffic in parallell with already existing streets and bridges, where the beams are mounted above the streets. The situations where more than 2 beams in parallel would be needed are: |
a) At stops where stationary cars must not block the way for those passing through. b) To enable cars to wait before being loaded at a busy station; a "buffer" segment. c) To enable faster "express" cars and booked cars to pass through a section where slower cars, running according to a schedule, has to berth at most of the stops. |
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Soft soil is a particular problem for ordinary high-velocity trains. It turns out that the great live mass of moving trains, coupled to high speeds, create shock-waves in the ground, similar to the waves of sea-going vessels. They are caused by the train´s pressing the tracks down into the ground, and are exacerbated by high speeds. Measurements in clay-rich soils in Sweden show that detectable waves from trains rushing by at speeds of 200 km per hour can reach 50 meters on both sides, away from the railway tracks. These waves can move the soils 20 millimeters vertically, and can thus damage buildings and cause landslides. Beamcars would not create this kind of problem, because they are much lighter, and would not normally be coupled together into trains. Nevertheless, the beam supports should of course be anchored as steadily as possible. If bedrock is not too far down, the beams would of course have to be attached as shown in A in figure 17. If bedrock cannot be reached, alternative B could be a solution. A pole anchored to a big, horisontal (or vertical) slab of concrete would be quite steady, for the same reason that the big keel would keep a sailing vessel reasonably steady. There is, of course, also the possibility of placing the poles closer together and let them support each other, either via the beams or (as complement to the beams) via underground interconnecting reinforced concrete slabs. These are shown in figure 18 below, except that the poles in the sideway view (view B at right below) would be further apart in reality. |  Figure 17 |
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 Figure 20 |
During heavy rains and sudden inundations, the water has to go somewhere. Like rivers, it soon finds the weakest points, where soil conditions offers the least resistance. The consequences, as illustrated in figure 19, is that roadbeds and railroad tracks are often washed away at those points, making them impassable. The beam systems adapt to these conditions. Instead of requiring indisturbed ground under a roadbed, they only need anchor points for the supports. If these points are selected with some care and made sturdier than the soil sorrounding them, the beam traffic is not hampered by the forces of nature. |
Finally, the straight poles (not the swan-necked ones) should have a circular cross section. The purpose is to easily enable the poles to carry crossbeams at any angle (B), as is shown in the bird's eye view of figure 20. This is particularly important in roundabouts, at car depots and at station areas with many platforms. figure 21 shows how round vertical beam-elements could easily be turned at any angle relative to each other. Since they are hollow, to enable the passage of communication- and powercables to the beams, this freedom of adjustability is a necessity for those poles that carry cables. |
 Figure 21 |
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 Figure 23
Figure 24 |
To reduce manufacturing costs and construction time, the pole should as much as possible have standardized parts and interfaces. Looking at figure 23, there should be a standard interface A between the pole and its foot. The lower part of a straight pole (1) should be about 3 meters in high and with an interface B that would allow the horizontal attachement 4 to be directly fitted to 1. Part 2 should have the required length (about 3.5 meters) to allow the smallest beamcars to cross each others´ path on a 2-tier pole. Interface C should of course be standardized, to allow the horizontal part (3) to be attached. Part 3 will need to be of varying length to:
The horizontal attachement 4 will come in 4 varieties. Looking at figures 23 and 24, you will find that there are those kinds that have:
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To accomodate subsequent changes of beam dimensions, because they have to accomodate larger (or smaller) beam vehicles, the hights of poles might need to be altered. This is done with the standard-length element 5. Finally, we have the poles that work in pairs to support 3 or more rows of beams, or in order to support each other when the ground conditions are not ideal. The horizontal element 3 could have a set of standardized lengths (L) or it could be cut to size when the beams are being erected. Because different beams might be dedicated to carrying only certain car sizes, or the beams are being erected in narrow city streets, it must be possible to adjust the beams sideways as required (s in figure 24.)
Telescoping polesThere would be no vertical adjusting screws or hydraulics in any of these column sections. Perhaps 2 or 3 horizontal set screws at the overlap, to hold the added section in place until the joint is welded all around. The final section at the top (with the horizontal arm) would be most carefully positioned to the required elevation. Finally, very fine, adjustment of the level of the beam could be made by adjusting screw supports between the beam and the arm of the column.
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 Figure 25 Figure 26 |
Required parts of these building elements could of course be attached to houses, as illustrated to the left. In general, any structures that are already in existence along the path of the beamtrack should be used as attachments for beams whenever feasible. The resulting savings in material would reduce the construction costs of the beam network. When planning for buildings along the path of intended beams, it would thus be advantageous if these buildings could help carry the beams as well. With suitable terrasses, the beamcars could dock directly at these buildings, as shown to the left (figure 26). With this solution, the beamcars would not need to be equipped with lifts. This concept of moving the stops from the streets to the buildings is quite interesting. One consequence is that the beams could conceivably be moved so high up in the air so as to be hardly noticeable from the ground
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| Copyright © 2004, SwedeTrack System. | Last Updated: 2007-01-17 | This site is maintained by Johnson Consulting |
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