[外文]The road network
In Beijing’s post-1949 road development, the opening of the east-west and north-south arteries became the most urgent work. This was vital for the development of new suburbs for industries, high level education, R&D and administration, as well as for residential use. As a result, the road mileage within the city and suburban districts increased 20-fold from 164 km in 1949 to 3276 km in 1991. The motorized vehicle numbers increased more more rapidly from 2328 in 1950 to 384 451 in 1990, as did total urban public transport users which increased from 29 million persons in 1949 to 3523 million in 1991. (Beijing Statistical Yearbook, various dates). The ratio of road mileage to car population increase is 1:8, and road mileage to public transport volume 1: 6. These too are common features of most Third World cities (Table 2). Beijing has, however, invested less in road construction. Bejing’s capital investment in urban transport (about 35% of which is spent on road construction and improvement) has been for many years less than 1% of the city’s total infrastructural investment. Most investment was in the first three years after 1949 and in the years since the Open and Reform policy was adopted in 1978. Quan (1988a) showed that in 1978-1988, the city invested a total of Y4.3 billion in transport construction, six times the annual average of the years before. In these 10 years, 6.23 million sq. m of urban roads had been added, or 38.7% of the total at 1978.
The major achievements in improving the urban road network are:
(1) opening up and/or widening of five east-west roads and one north-south trunk road;
(2) construction of ten arteries of 6-10 km in newly developed residential areas, including six north- south and three east-west district roads;
(3) in the suburbs, 13 main radiating roads have been built to link new developments there with the Old City;
(4) a number of ring roads have been constructed to reduce traffic in the Old City (Figure I). They are the Inner Ring Road, the main artery of the central area, which is 19 km long; the Second Ring Road of 23.7 km, on the former wall of the Old City (completed in 1993); the Third Ring Road of 48 km, completed in 1981 which serves mainly as the link between the suburban districts; and fourthly, the Fourth Ring Road of 65 km, partly completed at present. The Fourth Ring Road is to serve mainly intra-urban and inter-urban freight transport. Over the Second and Third Ring Roads, by 1989, 40 flyovers had been completed at busy road junctions (Figure 1). This system of ring and radial roads is basically copied from the Soviet model of transport planning.
Thus, post-1949 road building has altered the old grid pattern of the city’s road network, to a mixture of ring roads and radial roads. The Third Ring Road marks the divide between the Old City’s grid pattern and the predominance of radial roads in the outer urban areas in the suburbs.
Another important feature of the road network is the emergence of a circulatory system for bicycles, reflecting the city government’s increased attempts to integrate non-motorized modes in its urban transport strategy. From 1949 to 1965, most new main roads contained 14-21 m wide lanes for cars, in single carriageways without separation for motorized and non-motorized traffic. With growing use of bicycles in the city, the first three-carriageway main road was constructed in 1965 which provides separations for the two different modes. It contains two motorized vehicular lanes of 14 m each, and two bicycle and cart lanes of 4 m each. In between them are green reservations 2.5-5.5 m wide. By the end of 1983, there were 100 km three-carriageway main roads which were increased to 242 km (173 km within the city and suburban districts) in 1991. China is still unique within the Third World in integrating non-motorized modes into its road construction programmes.
Urban transport conditions have deteriorated due to rapid growth of motor car ownership and transport demand arising from economic and population growth, yet the imbalance in spatial growth of the network is partly responsible. A report of the Civil Engineering Bureau of the municipality revealed that there were 2000 km of roads (77.3% of total) within the planned urban areas (an area of 650 sq. km at the centre of the municipality), but their spatial distribution is however highly uneven. Within Second Ring Road were 747 km (36.1%) between the Second and Third Ring Road, 426 km (20.6%) and between the boundary of the planned urban areas and Third Ring Road were 896 km (43.3%).
Within the central area (the Old City of 62 sq. km marked by the Second Ring Road), main road density (roads of 7 m width and above) is the highest of all the urban zones, yet the quality of its roads are low. Main roads, however, only accounted for 9% of central area roads and it has few through-roads. The Old City, nevertheless, accommodated 28.7% of the urban traffic and was the origin of 53% of the commuting trips of the city. Its road network had already reached a capacity of 90% and yet its traffic volume was still growing at a rate of 4.6% per year, exceeding the city average of 3% (Quan, 1990a). Traffic surveys in 1986 and 1987 show that within the Old City, the speed of motorized vehicles on main roads dropped 40% in one year alone, to an average of 20 km/hour, while on 23 main roads it was only 10 km/hour. Inadequacy of main through-roads, arising both from the need to preserve the Forbidden City and San Hai, as well as high costs and problems of resettlement of the densely populated areas affected by road widening schemes, have constrained urban transport improvement in old Beijing.
As the Inner Ring road is still incomplete and of low standard due to the high costs and difficulty of demolition of existing housing, most inter-district traffic has to use the Second Ring Road. Traffic surveys indicated that 93% of the vehicle flow of the city is in an east- west direction and 25% of the inter-city flow passes through the inner city. This pattern of traffic flow is at conflict with the traditional street pattern of the Old City. A higher standard Second Ring Road and a completed Fourth Ring Road are certainly necessary in order to improve the situation. The standards of the radiating roads are also low. They mostly contain only two lanes for motorized vehicles, and sections on the inside of the Third Ring Road are still largely uncompleted.
Of the 2000 km of roads within the planned urban areas, only 824 km are of a width of over 7 m and could be used by motorized vehicles, including 100 km of high standard roads with four lanes and a total surfaced width of over 21 m and 235 km of 12-21 m width roads, which allow for some separation of motorized and non-motorized traffic. 60% of the road network are, therefore, below 7 m in width and cannot normally be used for motorized traffic. Only about 497 km may be used by ambulances, fire-engines and refuse collecting vehicles in emergencies. The remaining 748 km are only used for bicycle and pedestrian traffic (Civil Engineering Bureau, 1987).[/外文]