Grade crossings are often replaced at the discretion of the roadmaster, and the surflaces are not necessarily replaced in-kind. Existing asphalt crossings, for example, may be replaced with panelized full-depth timber. BN has standard plans for a number of crossing types- anywhere from the standard minimum 16-foot timber crossing, for farm or private crossings, to a variety of rubber surfaces, from wood-shimmed to full-depth, to concrete crossings for wood and concrete ties.
When selecting a replacement type, field supervisors are free to choose the appropriate surface for the prevailing conditions, within reason.
Although no longer in BN’s standard plan, there are some locations, such as industrial tracks with light highway and train traffic, where asphalt with a flange and header rail may be the most appropriate surface. In most cases, through, only about 10 % of the asphalt crossings come back as asphalt when renewed.
Most of the shimmed four-inch timber crossings that are reinstalled as full-depth timber. Although four-inch plank crossings are no longer in its standard plan, BN does not prevent field supervisors from ordering them. «If they really think they have to have something other that the standard plan, they can order it,» he says. At present, the bulk of BN’s crossings are full-depth timber, which, he says, may be the best type for light highway and heavy rail traffic conditions.
In spite of their attention to the difficulty and the expense of maintaining grade crossings, engineers are quick to admit that railroads do a poor job of collecting data on the condition of grade crossings, and they don’t really know what to expect of the available materials. To remedy this, AREA Committee 9, Highway-Rail Crossings, has begun working with the American Society for Testing Materials come up with crossing-material performance specifications. Lab tests will include wear cycles, impacts, of various chemicals, such as salt and soda ash, and various surfaces’ load capacities. While these tests won’t tell engineers exactly what will happen in the field, they will give them some parameters to work within.
T e x t 3
Series 300 Paves the Way
Known as Super-Hikari, the 16 – car Series 300 train was developed and entered revenue operation on Central Japan railway with the speed of 270 km/h.
Each Series 300 train is made up of five three- car sets and an independent driving trailer.
Four 300 km. asynchronous traction motors are used on each of the 10 powered vehicles, giving a total continuous rating for the train of 12000 km.
Car width and Series 100 sets, but the new trains are 350 mm lower, the smaller cross-section giving less wind resistance. The train also has flush-fitting doors and shielded under floor equipment to reduce drag.
Use of aluminum alloy body shells and asynchronous three-phase traction motors has cut the weight of the Series 300 by 25 per cent. A substantial saving has come from a new seat form 28 to 12 kg.
Smaller wheels are used to suit the lower body profile. Three specially –developed low-noise pantographs are fitted to each 16-cra train, each mounted in a shielded turret. As a further saving, the production- build train sets are normally run with only two pantographs raised at any time.
Whilst the primary aim of the Series 300 design has been faster speed, the passengers have not been neglected. Each train set carries 1123 second and 200 first class passengers.
Every other vehicle includes special seats for handicapped people and babies.
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