Читайте также: |
|
1. Translate the following words and memorize them:
pothole trash to deteriorate to patch to schedule | edge snow fence snowdrift snowplow sealing |
2. Match the English words with their Russian equivalents:
1. traffic facilities a) бульдозер с прямым отвалом
2. drain clearing b) ремонт выбоин (ямочный)
3. emergency maintenance c) разрушенные участки
4. pothole patching d) по крайней мере
5. to scatter salt e) накапливать
6. major failure f) очистка дренажных канав
7. routine maintenance g) серьёзное разрушение
8. worn spots h) разбрасывать соль
9. straight-blade dozer i) текущий ремонт
10. at least j) транспортные сооружения
11. to pile up k) срочный текущий ремонт
Reading task
3. Read the text carefully and do the tasks that follow:
The life of a road structure depends on the quality of its maintenance and minor renovation. Maintenance keeps the roadway safe, provides good driving conditions, and prolongs the life of the pavement, thus reducing the road investment. Maintenance consists of activities concerned with the condition of the pavement, shoulders, drainage, traffic facilities, and right-of-way. It includes the prompt sealing of cracks and filling of potholes to prevent water entering through the surface, the removal of trash thrown on the wayside by the traveling public, and the care of pavement markings, signs, and signals. In rigorous winter climates, substantial effort is required to remove snow and ice from the pavement, to scatter salt for snow and ice removal, and to spread sand for better traction.
In many countries an increasing share of road budgets is being allocated to rehabilitation and maintenance of existing roads, rather than new road construction.
Routine maintenance refers to activities such as grading, grass cutting, drain clearing, pothole patching, and shoulder repairs, which are performed at least yearly if not more frequently. Periodic maintenance activities are typically scheduled over periods of several years and include resurfacing and bridge repairs. Rehabilitation involves more substantial intervention to strengthen a road, repair structural defects, and restore the road to its initial condition, often after it has deteriorated to an "unmaintainable" standard. Rehabilitation sometimes also includes changes or improvements to previous characteristics, for instance, by widening, making small alignment changes, or providing footpaths.
Other maintenance activities include seasonal maintenance, such as snow clearing and flood repairs, emergency maintenance to restore roads after major failures, and the regular maintenance of road signs.
Repairing damage and resurfacing. Gravel and other similar type roads have to be smoothed quite often. Surfaces and edges of bituminous materials are repaired by patching with new material where worn spots develop from travel or because of weak spots in the ground underneath. Every 10 or 15 years many roads with bituminous surfaces are resurfaced completely.
Workers repair concrete pavements by digging out broken sections and putting in new concrete. They often repair cracks by filling them with asphalt. Many older concrete pavements must be resurfaced completely.
Deteriorated pavements can be reconstructed in several ways:
- the surface can be treated to improve its characteristics;
- the existing course can be overlaid;
- the damaged layers can be removed and replaced;
- the existing wearing course can be remixed with additional materials.
Clearing ice and snow. Most roads and highways must serve the year around. So they must be kept free from snow and ice in winter. In some places, snow fences are put up. These are thin pickets wired together and placed parallel to the road, on the side from which the storm winds usually blow, and about 50 to 100 feet (15 to 30 meters) from the road. Snowdrifts then do not pile up on the road.
V-shaped or straight-blade dozers clear the roads when it snows. In deep drifts, special snowplows are needed.
Often roads and highways that are slippery from ice and snow must have salt, chemicals, sand, or cinder spread on them to keep them passable.
Дата добавления: 2015-10-30; просмотров: 152 | Нарушение авторских прав
<== предыдущая страница | | | следующая страница ==> |
Pre-reading tasks | | | Comprehension check |