STUDY ON UNDERGROUND LIGHT RAIL TRANSIT SYSTEMS IN JAPAN Misao Sugawara Japan Railway Technical Service TSK Building, 8-13, Hongo 4 chome, Bunkyo-ku, Tokyo 113, Japan. 1. INTRODUCTION In Japan, monorails are being used as an urban public transportation system at four different localities where there is a medium amount of traffic demand, while automated guided transit is being used at five different locations for the same functions. In a few cities, there is the likelihood of linear motor light rail transit being adopted as a means of medium-capacity urban transportation.ci) Light rail, visualized as a smart high- performance streetcar, is also currently in service in five cities.(21 There is much latitude in the transport capacity of light rail transit, and as it is more advatangeous than rubber- tired automated guided transit, with respect to constuction cost and energy consumption, its wider use can be expected in the future. It is planned in Japan to realize a sizable cut in subway construction cost by means of small-scale linear motor subways, and comprehensive research is being conducted, including test runs on an experimental track in the Osaka area.(3) As to the operation of medium-scale guided transit systems driven by linear-motors on elevated tracks, their practicality has been studied, with running tests on experimental tracks in the Kumagai area. The author will give an overall description of the research and development on medium-scale guided transit systems in Japan, with exphasis on the samll-scale subway driven by linear motors and through a comparison with other modes, give his views on its future prospects of medium-scale transit. 2. THE SITUATION OF LIGHT RAIL TRANSIT IN JAPAN Light Rail Transit (LRT) is a generic name for systems pro- duced by improving streetcars so that they will ride more comfortably, weigh less, consume less energy, and have a higher outpout. Many of these systems are operated on rails on ordinary or exclusive roads in the form of articulated vehicles or in a train of two or more individually connected vehicles. These systems have the characteristic of being rather inflexible on 235 3-16-7 M. Sugawara such occasions as route change, since they are operated on fixed rails. However, the costs for their facilities, such as tracks, are lower than those for ordinary railways. The overhead railways recetly constructed in Manila and in Dockland in London, with their routes entirely separated from surface traffic, are also called LRTs, and use rails and iron wheels. This is because they are smaller in scale and weight and have a higher performance than ordinary high-speed railways. The name LRT thus has a wide range of meanings. However, it can be said to denote systems that use iron rails and iron wheels to support vehicles that are lighter, smaller, provide better riding comfort, and have a higher performance (in such respects as automated handling and energy conservation via utilization of new technologies) than ordinary railways. In Japan, track-related transportation systems, which are entirely separated from road-surface traffic, play a key role in urban transportation. In this paper, therefore, the author will describe the development and, future prospects of new guided transit that can carry one-way 30,000 passengers or less per hour, including systems supported by rubber wheels. In connection with the development of new transportation systems in Japan, the development of new technology has been a facal point as well. Consequently, the main emphasis has been on building medium-scale guided transit systems with new mechanisms. The guided transit system is characterized by its segreta- tion from road transportation. This gives rise to fast, reliable service with the added merits of greater safety and energy conservation also, there is less damage to the environment. On the other hand, the construction cost of the infrastruc- ture within urban areas is continuing to increase, even up to 40 billion yen per kilometer for some lines. In spite of this, subways are being built in nine large cities in Japan, due to the direct and indirect benefits derivable, with subsidies from the central and local governments making up 59.85% of the cost. In the large cities in Japan, railways handle a major por- tion of the urban traffic, with organizations such as JR, private railways and metropolitan railways making improvements to realize speedier service, better riding comfort and less energy consumption. In the local cities, railways have not always fulfilled their functions as urban modes of transport. However, they are 236 M. Sugawara now promoting a policy that will give easier access to their facilities, by increasing the frequency of train operation and establishing new stations at points where the distance betwee two adjacent stations is long and the possibility for urban develop- ment around the new station expected. Among guided systems those which use rubber wheels have been adopted for monorails and for a subway in Sapporo, and are regarded as new 1.a transportation systems. 1 One of the big aims of new as transportation systems is 06 Nex Trntporution SYStam ICat. 11 0.7 to select an appropriate Nev Transportation SYSIen (Cas. 21 scale of operation that n 0.6 $ 05 corresponds to sp transportation demand, with 0.4 --21.2222a_ ~ 0.3 the idea of creating a more New Transportation System IC., 3) economical transportation • 0.2 system. 01 4 6 12 16 20 24 28 32 36 40 44 48 52 56 60 64 Under a given condi- Vo4mw of trampor la' ion per peak Mr/ — tion, the transportation J But New lrrnsportalion mis, cost per passenger-kilome- / Monorail SuCway ter for each transportation mode is calculated (see Fig.1), and the economical criteria for monorails, Fig.1 Transport capacity and medium-scale automated cost for each type of guided transit and buses transportation system obtained. Monorails and medium-scale automated guided transit have the characteristic of being easy to install on roads, since they have a shorter turning radius. Also, on the basis that these systems are to be constructed for the purpose of relieving traffic congestion, monorail systems (and automated guided transit systems) constructed on roads in city planning areas are able to receive subsidies for their infrastructure cost (equivalent to 44.9% of the total construction cost) from the central and local governments, in accordance with the Urban Monorail Construction Act passed in 1972. This rate of subsidization was subsequently revised to 57% in 1987, and applies also to medium-scale auto- mated guided transit. Therefore, almost all projects are now planning to build transportation systems on the surface of roads. 237 M. Sugawara In recent years, the development of smaller subway has been promoted to reduce construction costs. To advance this cause even more, the adoption of linear motor driven vehicles is being studies, with tests being carried out on test tracks. By using linear motor driven vehicles, train height can be further re- duced, steep grades and sharp curves made negotiable, and con- struction costs lowered. Furhtermore, this concept is adaptable to medium-scale guided transit systems on viaducts, and relevant experiments have been conducted on test tracks. 3. GUIDED TRANSIT SYSTEMS OF MEDIUM-SCALE ON THE ELEVATED TRACK The first monorail in Japan was constructed at Ueno Park in Tokyo in 1957. Some others were built at other recreational facilities later on. As a regular mode of public transportation for the first time, Tokyo Monorail was constructed between Haneda Airport and the centre of Tokyo in 1964. Tokyo Monorail extends 13.0 km and is a mounting-type monorail. This line connects JR's Hamamatsucho Station in downtown Tokyo with Haneda Airport in 15 minutes, and carried 86,000 passengers per day on average, serving as an important airport access. The second monorail constructed for public transportation was the 6.6-km Shonan Monorail completed in 1970. This line runs between JR's Ofuna Station and Enoshima-kaigan in 13 minutes, and was originally a test case of the hanging-type monorail. Recetly, the pupulation alongside the line has risen, resulting in the number of commuters increasing to an average of 22,000 per day. Under the Urban Monorail Construction Act of 1972, urban monorails in Kitakyushu city and Chiba City (partially) were completed, and construction is under way in many other areas such as Naha City, Osaka Prefecture, and the Tama area of Tokyo. The main features of these monorails are indicated in Table 1. As to the medium-scale guided transit systems other than monorails, the systems which are now in operation, or under con- struction or having their construction plans confirmed, are as shown in Table 2. It was decided in 1986 to build an automated guided transit in Hiroshima, and in 1987, it was decided to build another one along the coast of Tokyo. However, since their details have not yet been finalized, they have been omitted from the Table. 238 Table 1 Construction and performance of monorails Classification Swaim oaration Under construction Items Chiba Pnf. Entworira Tokyo Monorail Shonan Monorail Kitakyu/ru City Osaka Pref. Okinawa Pm). Tokyo Chia City Kitakyushu Chiba Osaka Okinawa Tame Management Tokyo Monorail Shonan Monorail High Speed Railroad Urban Monorail High Speed Rlya Urban Monorail Urban Monorail Tam Naha Monorail Line Haneda Line Enofhima Una Kokun Line yamanote Une Osaka Monorail NorthSgsarb Une 0. 0, rry rrm.l (Tamponry name) 111 Chiba Sutton HbamembaUonho Kokun — CnIshIrodel Osaka Airport KamI4lttlal Section Oluna — Enoshima Airport — Ter. — Hanede — Kikugaokba (2) Chun Minfo — Ward larakl — Tama Centre — Kanchomr Ili Routa length (km) 13.0 6.6 8.4 13.4 14.1 16.1 I •iq 121 13.4 Authorized dale Dec.