A.30
the difficulties of the transition from the old narrow gauge
system to the new stamdard gauge system. In addition, cars
of this width would be more difficult to accommodate in the
narrow streets of Western District and would increase the
width of the ramps in Des Voeux Road Central.
Cars wider than 2.3m could also be operated on the existing (1.067m) gauge if tracks were relaid throughout with wider clearances. However, this concept retains many of the dis-
advantages of the regauging concept. The ability to use the existing tracks and the feasibility of making early improvements
are major potential advantages of the LRT concept in the Island
Corridor. It is considered that the adoption of a vehicle just less than 2.3m wide on the existing track gauge permits these advantages to be realised, while gaining a worthwhile advantage
in terms of cost and capacity compared with the existing vehicle
width.
A.31
It should be noted that the dimensions of bored tunnels for
such cars would be determined principally by the height of the car and overhead wire. It appears that the tunnel
dimensions would be capable of accommodating a car up to 2.65m wide with a side walkway in the tunnel. Thus if and
when operation completely in tunnel were eventually adopted, a second generation of (rail rapid transit) vehicles could be
built to a width of up to 2.65m. This consideration should be
borne in mind in determining clearances on tunnel sections of LRT line that would form part of an ultimate rail rapid transit line. It should also be noted that side-by-side
construction of running tunnels in Western District would be
possible if the rolling stock were no wider than about 2.5 metres.
Roof Height
A.32
To economise on tunnelling costs, the car should be designed to be as low as possible. The Tyne & Wear Metro car, for example has
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