Urban Traffic in Japan

1.1 Urbanization and transport demand

Рис.13

Population concentration stemming from economic growth is a worldwide phenomenon today. Japan is no exception, with its urban population rapidly increasing along with the development to a higher level of industrial set-up.

Particularly conspicuous has been the rapid growth of the population in the Metropolitan area centering around Tokyo (рис. 13) sphere by sphere, starting out from the city center for the past ten years. The outskirts of Tokyo is now organized to the distance of 30 to 40 km from the city center and is nearing now 50 km. And along with this population concentration, the transport demand in the city suburbs has been steadily increasing (рис. 14), almost doubling in these ten years, at a rate exceeding that of the popu­lation growth.

The peculiarity of this transport demand lies in the fact that it is concentrated in the morning and evening commuting hours. As a matter of fact, in these commuting time zones of four hours, as much as 50 per cent of the total passengers are carried. Naturally, the urban traffic problems must be solved with the massive traffic of commuting hours taken as the focal point.

Be that as it may, the passengers carried in and around Tokyo number as many as 30 million a day, or 30 per cent of the total passenger traffic of the nation. Its growth rate has been so high as to exceed the ever-expanding transport capacity, to crowd up all sorts of conveyances.

Рис.14

Thus, urban traffic has become one of the biggest problems facing the nation today.

1.2 Transport modes in and around Tokyo and the Railways

As to the means of transport in and around Tokyo, there are railways, surface electric cars, trolley buses, omnibuses, and motorcars. Shares of these transport mean in the total traffic volume are illustrated below (табл. 4). The railway occupies 64% far exceeding the average nation-wide percentage of 45%,

Accountable for this is that the railway network in and around Tokyo is well developed, as well as that of the railways, as explained later on, is most suitable for service in urban areas, because of its ability to carry on mass transport with great punctuality.

Таблица 4

Means	Nation-wide (In 1, 000 persons)	Ratio (%)	Metro­politan traffic sphere (In 1, 000)	Ratio (%)	Kinki traffic sphere (In 1, 000)	Ratio (%)
JNR Private railway Subway	18, 416 16, 238 3, 310		9, 582 7, 092 2, 080		2, 716 4, 990 1, 030
Total	37, 964		18, 754		8, 736
Surface trams Trolley bus Bus Hire cars Taxis Others	5, 344   28, 924 11, 798       84, 369		1, 869   6, 011 2, 685     29, 319		1, 833   3, 230 1, 488     15, 287

The railway when compared with other surface transport media is superior in mass transporting capacity, accuracy in service and safety in operation. It is, on the other hand, inferior to the others in branching — off ability and extending capacity. However, when we consider that the traffic demand is concentrated in fixed commuting time zones, as stated before, and the passengers' traveling distances are more or less un­changing, — that is, they are season-ticket travelers, we can easily conclude that what is most required of a transport means in urban areas is its mass transporting capability and speed.

Comparing the transport capacity of a railway route and a motorcar transport route, we find the former is far superior to the latter. For against the railway's 100, 000 passenger/hour, it would take motorcars of 100-passenger capacity to be run every 30 seconds to produce 12, 000 passenger/hr. The railway thus is incontestably superior to the motorcar in transporting capability in per area unit occupied.

Then, the scheduled speed of each transport mode during the commuting hours in and around Tokyo is a vital factor in that it determines the extent of the city make-up. The fact that the speed of the commercial bus is about 15 km/h against the railway's 30/40 km/h (табл. 5) goes to show that the railway is the most fitful means of mass transport for passenger service in Tokyo and its environs, capable of satisfying the transport demand most effectively.

Таблица 5

This is clear from the sprouting out of apartment complexes in the suburbs of Tokyo, too. How that a city is developing centrifugally along the railway, the demand on the railway is expected to grow more and more.

1.3 Transport energy and cost

It is not easy to compare strictly the energy consumption by various transport modes, as different kinds of motive power and transporting system are used. But, when the electric rail-car railroading and the motorcar transport in Tokyo and its vicinity are compared, we find the energy consumption of an electric railcar to be 15 kcal/passenger km against a commercial bus's 60 kcal/passenger km, only about one fourth.

The transport cost is an important factor too in making a comparative study of various transport modes. Although the cost largely fluctuates depending on the price of land, the extent of facilities used, and the utilization efficiency of the rolling stock, we find the transport cost of the railway is about one fourth of that of the motorcar (табл. 6).

Таблица 6

In this comparison, nation-wide averages are taken. As the land price is extremely high in Tokyo and its environs, the transport cost would be much higher than is given in the table for a transport mode with a capacity low in terms of per area unit occupied.

All this goes to show that it is more advantageous to boost the transport capacity of railways than that of any other mode in urban areas.

For railway transportation, usable are various forms, such as locomotive-hauled trains, diesel railcar trains and electric railcar trains. However, as a great number of passengers are to be carried for comparatively short distances in urban traffic, it is necessary to use a means of transport that satisfies the following conditions:

(1) To carry on frequent service, the rolling stock to be used must have a high acceleration and deceleration characteristic.

(2) The rolling stock must have a high transport capacity per area unit occupied.

(3) The rolling stock should inflict less public nuisance — that is, make less noise and not pollute air by its exhaust.

All these taken into consideration, it can be said that none other is more suitable for urban service than the electric railcar train.

So it is that the train service in our cities and their suburbs are performed almost exclusively by electric railcar train. JNR has about 4, 000 and private railways 3, 000 electric railcars put into service to meet the demand in and around Tokyo.