Imagens das páginas
PDF
ePub

Traffic on the Edinburgh streets is of so light a nature that no particular deductions can be drawn from types of pavement in use. As stated, the principal street, Prince's Street, is paved with hard wood. Some of the adjacent streets are surfaced with rock asphalt, and usually in the central portion of the city granite block is employed, frequently with gravel or sand filled joints, permitting a growth of grass between the blocks in some of the residence streets where no traffic whatever existed during the summer. The newly-built outlying districts have very largely macadam streets. Heavy granite curbs are usually employed with a granite gutterstone having frequently a dressed concave channel. The main roads connecting the city with the surrounding country showed some very fine examples of bituminous construction.

CHAPTER II

FRANCE

France has one of the most thoroughly organized systems for control of roads of all types to be found in any country, responsibility being divided between the state departments and their subdivisions, including municipalities. For the purposes of government, the entire Republic is divided into eighty-six territorial units, called departements. Each departement is a political unit and has a governor appointed by the central government called the prefet and an elective general council. In subdivisions of the departement the road control is carried out through an engineering organization responsible to the Governor and General Council, so that not only the highways of the great cities and those of national importance are under control, but each read down to the smallest section connecting two villages. A large part of all government engineering work is carried out by the corps of engineers of Bridges and Highways, a body of national civil engineers having direction, not only of the highways, but of the various civil engineering works which are administered by the French Government.

The best and most thoroughly organized city in France is, of course, Paris. Similar organizations on a smaller scale will be found throughout the other principal cities of the country.

PARIS

Probably the second city in importance in Europe at the present time, as it has been for years past after London, is Paris, although closely pressed for supremacy by Berlin. Including suburbs immediately beyond the city limits, the metropolitan district has a population of over 3,000,000 and an area of about 20,000 acres or 31 square miles. It contains the densest population in all Europe. It occupies a generally low plain on both banks of the Seine just below its confluence with the Marne, extending back to a series of surrounding hills. The average altitude ranges from 120 to 200 feet above sea-level with a maximum of about 420. Lying well inland and to the south of the severer climatic conditions of England and north Germany, it has generally mild weather with a mean annual temperature of 51.3 and mean temperature in winter of 37.8 and in summer of 64.5. Extreme summer weather sometimes produces heat and drought approaching that often experienced in New York; but there is seldom any severe winter weather and snow-falls are infrequent.

Paris, in spite of its antiquity, possesses a better city plan than many of the other great cities of Europe, having been entirely reconstructed in the last century by the laying out of a great system of radial and circulating avenues giving direct traffic lines between the various centers of activity and producing a plan in general similar to that of Washington, with the addition of a series of boulevards on an inner circle occupying the site of the city wall of the old city of two centuries ago, with another roadway on the outer circumference along the line of the existing fortifications which still surround it. These, which at present distinguish it as one of the few walled cities of Europe, are shortly to be removed and a broad parkway will take their place. Its situation as regards internal traffic is somewhat similar to that of London in that it extends in a generally

easterly and westerly direction along both banks of a navigable river;

having the most important business district on the north bank with the ancient city of Paris occupying an island and the region in its vicinity near the center in somewhat the same relation to the rest of the city as is that of the City of London to the boroughs. It is reached from outside, as is London, by a series of railway terminals distributed around a circle at a distance of a mile or two from its central district, and it is, with London, one of the two European cities whose street traffic and pavement problems are fairly comparable to those of New York. In addition to a number of underground railways, extensions to which are now being constructed, street passenger traffic is taken care of both by tramways and motor omnibuses. The former extend generally through all parts of the city, but at the present time there is a somewhat chaotic condition; the old lines have had various forms of power, including steam, compressed air and both the overhead trolley and underground slot system with the slot contiguous to one tram rail, which forms part of the conduit construction. At the present time all these old systems are being reconstructed on the plan of the New York and London tramways with an underground central slot conductor. Motor omnibuses, which are very largely used, are single-deck affairs of a type similar to some that have been introduced on Fifth Avenue and carry a large traffic at a very rapid rate of speed. All motor vehicles run through the street at somewhat greater speed than is observed in London and New York and with considerably less police control.

Paris streets may be graded in importance and size, the widest and of the first importance being the boulevards. Of these, the old boulevards of the inner circle have a width of 150 feet or more with double roadways divided by a central line of safety isles and electric lights and bordered on either side by wide footways lined with large shade trees and of such size as to provide sufficient width for foot-passengers as well as for many sidewalk cafés and other areas restricted to private business. Other boulevards and avenues of later construction are straight diagonal streets which have been cut radiating from one traffic center to others. In and between and connecting these most important thoroughfares are many broad avenues, and finally the space between them is subdivided by streets and alleys, many of considerable local importance but largely relics of the old city plan, which was amplified by the construction of the first-described highways. The plan adopted for Paris was based on a desire to make efficient control of street mobs possible, just as the first smooth pavements were said to have been laid to do away with the existence in the street of material for the construction of barricades.

At the present time the streets have a total length of 632.97 miles.
The pavements are classified as follows:

[blocks in formation]

The proportion of pavement annually relaid or repaired, with its cost, is as follows:

[blocks in formation]

A few of the unit prices prevalent at present for various classes of pavement are given below:

[blocks in formation]

Works of maintenance and construction on the highways of Paris are executed as part of the duties assigned to the charge of the office of Public Ways, Lighting and Metropolitan Railways as a division of the Department of Works of the city. It has one of the best organized systems encountered in any European city for the control of public works, which may be said of the entire Republic of France, into which the Department of Works of Paris fits as one of the units in the general governmental system. It has been thought of sufficient interest to include in the Appendix to this report part of the latest annual report describing the public works of Paris and its form and extent of organization.

The office of Public Ways divides its paving work roughly into three classes: first, the construction of new pavements either on newly opened streets or where an old pavement is removed entirely to make way for one of the better class; second, the renewal of an old pavement, which involves usually the removal of the entire surface and its replacement with another on the original foundation, which latter may or may not require some resurfacing; and third, maintenance repairs on streets in generally fair condition. The first class of work is done by contract; the second by contract with the exception of about 25% of the work of relaying wood block, which is done by the department forces; and the third, by contract in the case of asphalt and to some extent wood and by city forces generally for stone and macadam. In addition to the roadway construction, the footways and alleys are newly constructed by contract and maintained usually by city forces.

During the past year 20-year contracts have been made for the relaying, over a period of seven years, with new asphalt pavements, of extensive areas at present unsatisfactorily paved with macadam, stcne and wood and including the maintenance for the entire 20-year period of these and the other existing asphalt streets. The contracts include the entire work planned throughout a given number of districts in the city, stating a definite proportion of the work to be accomplished each year, and the contractors have bid a percentage reduction on a carefully made schedule of unit prices for all classes of labor and materials, the contract including exact details in as far as they can be anticipated of all parts of the work to be accomplished and all conditions that are expected to arise. This form of contract and specification being one of the most extensive and complete encountered in any European city, has been thought of sufficient interest to include in whole in the Appendix. For the repaving of wood block streets contracts are also made, but the city purchases the wood and manufactures the blocks at its own plant. The material used is very similar to that in the English wood pavements, but as, until recently, it has been treated only by a dipping process allowing an absorption of merely a few pounds of creosote oil to the cubic foot, the wood paved streets have shown many signs of rapid decay. The plant equipment, which is most extensive and complete, has had added to it a tank for pressure treatment, and the authorities are arranging to impregnate

the blocks with from 8 to 10 pounds of oil per cubic foot, in accordance with the English practice.

The estimated life of different classes of pavements is:

Stone block..
Macadam.
Asphalt..
Wood....

15 to 30 years
5 years

10 years

8 to 15 years

In the case of the stone and wood block roadways lasting for the maximum periods indicated above, the material would have been entirely relaid or renovated in the process of maintenance before its expiration.

Paris has an extensive storm water sewer system through its main drainage channels necessitated by its low situation and tendency to flood in times past. The existence of these large drainage channels under the main streets has been utilized for placing within them, whenever possible, water-mains and electric cables. These, however, exist to only a limited extent in the total mileage of streets, and sanitary sewers are much less developed than in some other modern cities. In many parts of the city buildings have no sewer connections and the contents of cess-pools, as well as other household waste, have to be removed by a system of wagon transportation by contract or, in some cases, by administrative organization. In general and wherever possible pipes for water, gas, electricity, etc., are laid in duplicate under the footways, avoiding all necessity of opening the roadway for house connections. Only in cases of absolute necessity are any such conduits under the roadways. Certain lines for high tension electric cables are placed in special masonry galleries. Gas mains are never laid in sewers or subways, but always buried in the earth. Tramways are partly municipally controlled and in part under private corporations. The paving in and between the tracks is done under the same control as the remainder of the street. It is the unanimous opinion of French engineers that asphalt is rapidly destroyed when laid in and between the rails of tramways. There is always employed in this area either wood pavement or, by preference, hard stone (trap or granite), in either case laid on a concrete foundation. Their rules require that the pavement shall be so laid as not to have any projections above the rail. The entire organization of public works in the city of Paris is shown in some detail in the report quoted in the Appendix. It indicates a highly centralized organization strongly contrasted with the scattering and independent control shown for London. The Department of Works of Paris is a special division under the Prefecture of the Department of the Seine. Under the direction of the department is a division of administration and one of engineering, the latter having direct charge of the construction of public roads, lighting, street cleaning, water supply and sewerage. An inspector-general with a deputy is at the head of this division of Paris street surfaces. Under him is a chief engineer of highways and lighting, the entire city being divided into seven sections each headed by a resident engineer. Other chief engineers are at the head of the work of street cleaning, lighting (inspection of gas and electric companies) and water supply and sewerage. Each chief engineer has his own staff of office helpers and special resident engineers for particular work or for the management and maintenance of work outside the city; but within the city limits all construction work is under the direction of the street surface resident engineers. Each in his own section has charge, not only of the work of paving, but the laying of water-mains and the construction of sewers. The work of gas and electricity can only be undertaken when duly authorized by him and under his inspection, so that he is absolutely responsible for all that concerns the pavement construction and maintenance. For the purpose of local self-government the city is divided into about twenty arrondissements, and the section of each resident engineer includes two or three of these.

« AnteriorContinuar »