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MonoMetro is a transportation planning company formed in 1997 to promote a new design of suspended narrow-gauge railway. Its main activity has been to promote this as an answer to London's congestion problems, but interest has also been shown in the system by other cities. MonoMetro claims its system would be cheaper to introduce than a tram as it would not be necessary to divert or strengthen sewers along its route and that it is also superior to monorail systems. The system infrastructure costs calculated on mean fabricated tonnage of steel and construction quantities reference a twin track system with a parallel platform station located every 750 metres. Costs including planning, required Acts of Parliament, professional and tendering costs, electrical supply costs and street diversion costs for central London implementation were estimated at £15 million per kilometre (2005 estimate).〔 Costs outside London must be based on approx 1000 tonnes of fabricated steel per km plus the local cost of planning etc. By comparison to tramway implementation MonoMetro costs around 60% of the cost of building a tramway. The difference however is that MonoMetro is a mass transit system offering 20,000 passengers an hour capacity, trams offer 3000 - 7000 passengers an hour capacity. ==Technology== The paradigm precedent for MonoMetro is that of the Wuppertal Schwebebahn, but the technology of MonoMetro is quite different. The trains are suspended from six-wheeled bogies (or trucks (America )) running along a narrow gauge ''pair'' of rails; MonoMetro is thus a railway and not a monorail. The rails have a concave cross section and the wheels a corresponding convex profile. The vehicle load hangs centrally from a pivoting joint located at the intersecting radial load lines of the wheels. According to the patent "()his configuration moves the pivot point away from the wheel-track contact point (as in the Wuppertal Schwebebahn) to the point of intersection of the radial loads through the wheels. There is no torque acting on the bogie frame causing loss of contact with the track raceway as would happen if the load and bogie assembly were rigidly connected". The patent compares this to monorail technology that instead require a much heavier guideway and heavier bogies to overcome torsional forces and also need complex superelevation to provide passenger comfort on corners. The patent says propulsion will be provided by linear induction motors. The rails have special end junctions and are laid along continuous rubber cushions along the beams, held in place by regular (Pandrol) railway torsion clips.〔 No details appear to have been published as to how track switching is effected. The continual infrastructure of beams and columns is entirely constructed from steel. Visually the columns have three distinct components: *The lower section, the Kinetic Impact Base (KIB) is constructed using a gussetted hollow box beam steel structure ring bolted to a foundation chamber. *A foundation chamber with standardized fixings connects the KIB to each of several different foundation types depending on location, sub-ground type, or directly set into bedrock when the top soil is very thin in rare locations. *The foundation systems, deep piles of varying types, percussed, bored, under-reamed, bucket bell type, or pre-fabricated foundations with submerged pre-cast inverted "mushrooms" ring piled with mini piles, or submerged ground beams able to step over unusual obstacles. Whatever the foundation location for whatever problem exists below the ground, there is a foundation design capable of stepping elegantly over it and closing the site of surgical intervention cleanly and elegantly within the streetscape. The essential difference between MonoMetro implementation and that of trams is the microsurgical construction limited to a local opening in the groundscape, creating the appropriate foundation type with foundation cap level with the ground ready for standardised fixing of the KIB. The KIB section is lightweight hollow pre-fabricated from steel plate with specialised internal divisions that is easily manoeuvered on site. The ring bolting to the foundation cap is slightly above the ground surface keeping the bolts dry and visible for inspection. Once bolted into place the KIB can be precision levelled and then concrete filled giving the mass required for impact resistance to collisions. Collision impact resistances satisfy regulations for civil structures adjacent to the full range of transport vehicle carriageways. After securing, the KIB ring bolt aperture receives a sacrificial urethane deflector profile designed to absorb the primary energy of impact through the vehicle chassis. There are four different deflector skirt profile types for differing locations appropriate to varying traffic speeds. These urethane skirts are also colour coordinated for visibility or aesthetic toning within the precise urban location. The middle section of the column above the KIB has two sections: *A lower parallel profile section that allows the column height to be cut for height adjustment that allows for ground undulation. *An upper tapering section of the column culminating in a double sided column head. This tapering element reduces the lower longitudinal dimension designed to resist the greatest forces upon the column... that of acceleration and braking, to match the dimension requirement of the column head fixing. The internal cellular construction lends maximum torsion resistance and resistance to longitudinal bending of the column. The tapering section, likened to the taper of a classical obelisk enhances the visual proportion giving an elegance to its appearance in the urban landscape. The column head offers a pair of fixings to which single or paired butterfly arms are attached using the same column for single track or twin track beams. The column remains the same for both types. The butterfly arms are reslilently connected to the column head using well proven SPS elastomer technology. Entirely concealed fixings give a seamless architectural appearance, uncluttered by the nuts and bolts normally associated with civil engineering structures. MonoMetro is civil engineering architecture. The junction between the butterfly arms and supporting beams is designed to allow for the principle degree of freedom of the beam, longitudinal plane rotation as the primary movement to be accommodated between the beam and column. The fixing is also designed to resist torsion and the longitudinal force of acceleration and breaking. There is also load sharing along the beamway that increases redundancy achieved with a patented consecutive beam junction that damps low frequency oscillations and distributes attenuated loads forward and backward along the beamway so a number of columns resist loading at any one time. The beamway is an advanced torsion resistant macro-cellular constructional assembly achieving longitudinal structural continuity with a patented junction between consecutive beam modules. The assembly delivers entirely accurate constructional alignment overcoming any variations in fabrication tolerances and longitudinal and torsional structural continuity at the same time as allowing longitudinal expansion and contraction through environmental temperature ranges. This continual beamway structure breaks free from the need of regular column spacing, this escaping the "post and lintel" characteristic common to all other beam carried transit structures. A permissible span of up to 33 metres under dynamic loading allows for optimising the spacing between columns for convenient ground positioning to avoid foundations clashing with sub-ground services. The design flexibility of irregular column spacing minimises visual impact and obtrusive collisions of the column footprint with existing urban features on the ground minimising the need for costly relocations whether it be a telephone box or an important data carrying fibre optic cable. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「MonoMetro」の詳細全文を読む スポンサード リンク
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