In 1887 de Smedt was followed as inspector of asphalts and cements by Clifford Richardson, who set about the task of codifying the specifications for asphalt mixes. Richardson basically developed two forms of asphalt: asphaltic concrete, which was strong and stiff and thus provided structural strength; and hot-rolled asphalt, which contained more bitumen and thus produced a far smoother and better surface for the car and bicycle.
One of the great convenient coincidences of asphalt development was that the automobile ran on gasoline, which at that time was simply a by-product of the distillation of kerosene from petroleum. Another by-product was bitumen. Until that time, most manufacturers had used coal tar (a by-product of the making of gas from coal) as the binder for road asphalt. As the demand for automobile fuel increased, however, so did the availability of bitumen and, hence, of good asphalt designed to the standards de Smedt and Richardson. This gave U.S. road builders a major advantage over their European counterparts, were still wedded to the virtues of the various natural asphalts, such as those from Neuchatel, Switz., an Island of Trinidad.
Richardson published a standard textbook on as paving in 1905, and the practice did not change greatly thereafter. The biggest change was in the machinery able to produce, place, and finish the material rather in the product itself. Toward the end of the century, were major movements toward the use of recycled asphalt chemical modifiers for improving bitumen properties small fibres for improving crack resistance. In addition developments in testing and structural analysis made possible to design an asphalt pavement as a sophists structural composite.
The first modern concrete roads were produce by Joseph Mitchell, a follower of Telford, who conducted three successful trials in England and Scotland in 1865-66. Like asphalt technology, concrete road building largely developed by the turn of the 20th century am restricted more by the available machinery than by the material. Problems were also encountered in producing a surface that could match the performance of the face produced almost accidentally by hot-rolled asphalt. For the following century the two materials remained in intense competition, both offering a similar product similar cost, and there was little evidence that one would move far ahead of the other as they continued on paths of gradual improvement.
Oral Presentation: MY SPECIALITY
ROADS OF BELARUS
The Speciality "Highways"
The Government of out Republic pays great attention to the road construction industry. The industry is developing at a rapid rate. The network of highways with hard pavements is increasing annually in our Republic, half of them are highways with advanced pavement. In the State Programme "Roads of Belarus" it is envisaged to secure communication between large economic centres of our country, to extend the construction of rural roads, to improve the quality of construction, maintenance of roads and special attention should be paid to the safety of traffic.
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The Faculty of Transport Communications was founded in 1978 as the Faculty of Hydro-engineering and road construction. In 1998 it was renamed into the Faculty of Transport Communications because of changes in the structure of specialities.
Now the faculty prepares specialists for all road-building complexes, including the construction of roads and airfields, bridges and tunnels, undergrounds and application of road-building machines.
The teaching process at the faculty is carried out by the following departments: Construction and operation of roads, Designing of roads, Bridges and tunnels, Building and road machines, Resistance of materials and theory of elasticity, Engineering surveying, Higher mathematics and English department.
The students are trained in the following specialities: Lifting-transport, building, road machines and equipment, Highways, Bridges, transport tunnels and undergrounds, Economy and organization of manufacture.
Highways is one of the leading specialities at the Faculty of Transport Communications. In the first two years the students of this speciality study many general subjects necessary for a skilled and all-round educated engineer. Specialization begins in the third year when the students begin studying designing, construction and maintenance of roads.
Having acquired theoretical knowledge the students have their practical training at the University laboratories, construction sites and different enterprises connected with their future speciality.
Much attention is paid to the scientific and research work of the students of this speciality. They carry out research work according to agreements with different enterprises under the leadership of the leading lecturers of the Department. Their research work is connected with problems of road construction materials, utilization of waste materials in road construction, the problem of road design in conjunction with road safety, etc. This kind of work helps future engineers to combine theoretical knowledge with practice.
Specialists in road construction field are in great demand. Every year about one hundred and fifty road engineers graduate from the University and the main task of the students is to do their best to become highly qualified specialists. They have all the possibilities to achieve the aim.
ROADS OF BELARUS
Belarus is fifteenth among countries with developed network of motorways by density of public roads per one square kilometer and twelfth by their length per one thousand of inhabitant
BACKGROUND
More than four centuries ago the first documents(statuses) for the state regulation of public roads and traffic rules were introduced in Belarus. In XVIII-XIX the Belarusian roads reached the European level. During the Soviet times a large-scale road construction ensured the creation of optimum network of motorways. Presently, having 207,600 square kilometres of territory and 10.5 million inhabitants, Belarus accounts for 53,500 kilometres of public roads. More than 67% of them are concrete or asphaltic concrete, 1,830 km of roads have four or more traffic lanes. The core of Belarusian motorway network is republican highways 16,382 km long.
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The main government document that sets out economic, legal and administrative principles of governing the country's system of motorways is the 1994 Law on Motorways. The Committee for Motorways under the Belarusian Transport Ministry oversees the branch that is financed from the state budget road fund.
TRANSEUROPEAN HIGHWAYS
The geographical situation of Belarus has predetermined its role of a transit state. The main Belarusian highway Minsk-Moscow was built before the World War II. In 70s the highway was extended to Brest within the project of large-scale construction timed to 1980 Moscow Olympics.
After the break-up of the Soviet Union, the Belarusian motorways became an essential part of the European transportation network. At the present, the major Belarusian highway is Ml (E30 by European classification). It links West Europe countries with Russia, crossing Poland and Belarus (606 km). In 1994 the country started the project of Ml modernization, funded with loans of European financial organizations. By 1998 reconstruction of the first stretch of the highway 234 km long was completed. Upgrading and improvement other parts are in progress.
Ml highway makes also a part of the Crete Corridor 11 that is considered by the European Union a priority transportation route due to the significance of East-West transport flows through it.
Another important Belarusian highway is M8 that is a part of the Crete Corridor IX and links Russia with Ukraine through Belarusian cities of Vitebsk and Gomel. The highway is 456 km long.
The 468 km highway Gomel-Vilnius-Klaipeda plays an important role in the Crete Corridor IXB, linking Russia and Ukraine with the Baltic states.
MANAGEMENT
Belarus' road maintenance system had been finally shaped in 1998. State-run companies (called Avtodor) distribute government orders among companies of different ownership thus making it possible to use the allocated funds efficiently and exercise control over fulfillment of road maintenance contracts. Magistralavtodor oversees maintenance of M highways which are 4,200 km long. Local motorways are run by six Regional Associations which are subordinated to local governments. The road branch of the country employs more than35.000 people.
V. Words and word combinations to be remembered:
highway
traffic
performance characteristics
vehicle
provide for
safety
asphalt-macadam surfacing
soil
stone aggregate
pavement
haule ,
construction site
prefabricated reinforced structures
Artificial structures
earthworks
gravel quarrying
stone crushing
scarcity
thoroughly
to undertake research
trench
road pavement ()
inventor
dig (dug)
ground
bottom
to give a camber
divert
to seep from above
pavement base
uniform thickness
slab
surf course
crushed aggregate
hard rock
granular base
roller
levelled and compacted formation
ensure
elimination
strength
assure
subgrade resistance
reliable
granular surfacing
sand base
subgrade stability
