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The characteristics of streets are – low vehicle speed, sharp turns (right angle turns) and very little road shoulder. Road shoulder is the patch of grass at the edge of the road to the drain on both sides of the road. All roads have shoulders. The emergency lane is part of the road shoulder for highways. Road shoulders purpose is to allow for service and emergency vehicle access. Road shoulders serve to increase the serviceability of the road and safety. The higher the permitted vehicle speed permitted on the road the wider the shoulder is. There is no restriction on road gradient (slope of road) and therefore line of sight. Such roads may be level or may be quite steep. There are no traffic lights. Streets are non divided.

Collector road collects traffic from all other streets. Its purpose is to channel traffic to other collector roads or higher class roads. Characteristics of collector roads are – wider than streets, higher speed limit, divided road, little or no sharp bends and lower road gradients. These roads are usually not divided. Generally there are no traffic lights on these roads. However in very large townships, there may be a few traffic lights due to the high traffic volume. In addition, the road may be a 4-lane dual carriageway. Due to the relative low vehicle flow rate and proximity to home/office, drivers tend to use their mobile phone more. Police frequently enforce the law regarding mobile phone usage on these roads. Red light cameras are usually placed on these roads too.

The collector roads in turn empty its traffic onto arterial roads at graded intersections. An intersection is a meeting of two or more roads (class of road irrelevant). It serves to link two or more suburbs together. A graded intersection is an intersection of two or more classes of roads. There are numerous traffic lights on these roads which serve to throttle the vehicle flow rate. Sometimes you will find that a street or lane connects directly onto an arterial road. This is due to lack of enforcement, oversight, poor town planning or lack of funds. You have to wait for ages in order to turn into the arterial road.

Arterial roads have low road gradients, smooth bends (less than 60 degrees), allow for higher vehicle speed, 4-lane dual carriageways and have lots of intersections and traffic lights. Such roads are wide, smooth in curvature and fairly straight, so drivers are always tempted to drive at higher speeds and therefore there are frequent speed traps on these roads. There are also red light cameras on these roads.

Highways are designed to link townships together and allows for high speed travel. These roads are usually 4 or 6 lane dual carriageways. Such roads may be wider (6-lanes) on some stretches and narrower (4-lanes) on other stretches. When townships are far apart and traffic flow rate is not high, 4-lane would suffice, otherwise it will be 6-lanes. The curvature is very smooth, usually less than 60 degrees. A first class highway would have bends no more than 45 degrees. But it requires lots of land and is very costly, so there is usually a compromise between 45 and 60 degrees. U-Turns are not allowed.

A major highway is very much a highway and there are no traffic lights and definitely no rural roads can connect onto it. Connection between a major highway and other highways or arterials is by entry and exit ramps only except for toll. There are lots of facilities along such highways such as rest stops, petrol, food and even lodging. In countries like Australia, the USA, etc, there are lay-bys where one can park the car to take photographs of the beautiful scenery. Generally, there are no direct U-turns on these roads, but they are often achieved by way of specially constructed underpass. Alternatively, U-turns can be achieved via exit and entry ramps. You can exit the highway via one leaf, pass the highway below and down the opposite leaf and travel in the opposite direction. A full diamond interchange is one where there are 2 loops on each side of the highway. If you exit the highway on one leaf and traverse all four leafs you will end up on the same side of the highway you originally exited from and traveling in the same direction. Just for information, a full diamond interchange requires at least 50 acres of land!

Roads are categorized into class type for design purposes. Each class has a different design specification. Roads are categorized to allow a systematic approach to its design and construction. By design, some roads will have more traffic than others and therefore we require a graded interchange (traffic light) to regulate/throttle traffic flow.

Due to variance in politics, existing neighboring land use and level of funds available, certain specifications may be altered or amended to suite local requirements. In developed nations, highways and roads are designed with the prime objective of ensuring free flow of traffic. Each country has its own set of guidelines for roads and town and country planning.

5. Look through the scheme and comments to it, say which group of purposes each passage corresponds:

Defining a road classification hierarchy can be undertaken for several purposes, many of which are interrelated and highlight the importance and complexity of defining the road classification appropriately.

At a fundamental level a road classification hierarchy defines:

the network in such a way that it facilitates the safe and efficient movement of vehicles as well as other roads users, such as pedestrians and cyclists;

relationships between different types of route, considering both local and regional needs.

The application of a road hierarchy may be used:

to assist in determining the purposes of the various roads in the network;

to allocate appropriate roads funding;

to define an appropriate level of interaction between the roadway and land use, design standards, operational matters and funding considerations;

to enable jurisdictions to ‘double-dip’ for funding where there is dispute or uncertainty regarding the classification of particular road segments

Road users have expectations when using roads within the network, whereby they perceive roads exhibiting certain characteristics to deliver a particular travel expectation. Road user expectations have an important influence on user behavior and performance in traffic. Therefore, having a well defined and consistent road classification hierarchy can reinforce road user expectations and improve the effectiveness with which the road network carries traffic.

Look through the scheme once more and make a conclusion why it is necessary to classify roads.

6. Read three texts devoted to the types of road hierarchies and fill in the gaps with the following words and word combinations (there is one wrong word in every row of the words):

1)through-traffic, traffic mobility, assigned, operate, interconnected network, land access, ranks, proportion, determine.

2)hierarchies, differentiating, segment of road, traffic, categorized, local government.

3)military situations, conjecture, individual variables, structural standards, load bearing and height restriction, surface type, the location, purpose of the classification, road mobility.

I

FUNCTIONAL ROAD HIERARCHY

A functional hierarchy is the most common type which … roads according to how the roads are expected to function with respect to local … . In doing so, it recognises that the roads form part of an … and addresses the competing road uses of mobility and access. Fundamentally, streets and highways perform two types of service, either providing … or … . The proportion of service they provide will … the rank each road is … in the hierarchy. Defining the hierarchy in this way describes how traffic should flow in a logical and efficient manner through the network, as well as how it should … and be managed.

II

ADMINISTRATIVE ROAD HIERARCHY

An administrative hierarchy assigns an order to roads on the basis of who is responsible for managing a particular …, whether it be Federal, State or … . In broad terms, the road system consists of National Highways, State Highways,

State Roads, Main Roads and Local Roads. Mistakenly, in such … State Highways, State Roads and Main Roads are often … using functional terminology such as “Arterial”. This misuse of functional terminology in an administrative classification undoubtedly leads to confusion in … these two types of road hierarchy.

III

STRUCTURAL ROAD HIERARCHY

Another, less common method of road hierarchy classification, is to rank roads according the … applied to a given segment of road. The structural determinants (geometric design) that classify a particular road may vary, depending on the intended …, and can include … or a combination. Variables that are often considered include road width, …, gradient, wet weather condition, … . Generally, a structural road hierarchy is most often applied in … .

There is some … as to whether structural considerations should influence certain functional classifications. By definition, the functional classification should be based purely on … – although the structural characteristics may determine how many of a certain road type are needed to perform a particular function.

7.Make up the following questions concerning texts above and answer

them:

1)the main principals of /what are /functional, structural and administrative road classifications;

2)be considered/these classifications/ entirely separate/should/If not/could you find /what interrelations;

3)as “state highway”, “state road” and “main road”/why the term “arterial” /instead of such terms /can’t be used;

4)according to /which of these classifications /everyday purposes of the average man /your point of view/is the most useful for.

8.Look at the list of fundamental classification criteria and try to match every criterion with its description.

Irrespective of the type of road hierarchy being developed and applied there are certain characteristics or criteria that are fundamental to all road classifications. It is important in reviewing the current status of road classifications that each be assessed on how well they satisfy these criteria.

Think about other criteria that you can add to this list.

9. Study the following terminology concerning roads, their types and parts and make up sentences using some of these words:

All-weather road – unpaved road that is constructed of a material that does not create mud during rainfall.

Adverse camber – the situation where the road slopes towards the outside of a bend, increasing the chance of vehicles travelling at speed toppling or skidding. Usually it is a temporary situation during road maintenance.

Byway – highway over which the public have a right to travel for vehicular and other kinds of traffic, but which is used mainly as footpaths and bridleways. Bypass – road that avoids or “bypasses” a built-up area, town, or village. Bottleneck – section of a road with a carrying capacity substantially below that of other sections of the same road.

Camber – the curvature of the road surface that encourages surface water to flow freely from the carriageway, or on bends angling of the surface to lean traffic “into the bend” reducing the chance of a skid.

Chicane – sequence of tight serpentine curves (usually an S-shape curve or a bus stop) in a roadway.

Chipseal – road surface composed of a thin layer of crushed stone “chips” and asphalt emulsion. It seals the surface and protects it from weather, but provides no structural strength. It is cheaper than asphalt concrete or a concrete, in the U.S. it is usually only used on low volume rural roads.

Corniche – road on the side of a cliff or mountain, with the ground rising on one side and falling away on the other.

Curb – edge where a raised pavement/sidewalk/footpath, road median, or road shoulder meets an unraised street or other roadway.

Curb extension (or also kerb extension, bulb-out, nib, elephant ear, curb bulge and blister) – traffic calming measure, intended to slow the speed of traffic and increase driver awareness, particularly in built-up and residential neighborhoods. Fork – (literally “fork in the road”) type of intersection where a road splits.

Guard rail – prevents vehicles from veering off the road into oncoming traffic, crashing against solid objects or falling from a road.

Green lane – (UK) unsurfaced road, may be so infrequently used that vegetation colonizes freely, hence “green”. Many green lanes are ancient routes that have existed for millennia, similar to a Byway.

Gutter – (UK) a drainage channel between the main carriageway and the edge of the road.

Interstate Highway System – United States System of Interstate and Defense Highways.

Traffic island – (UK) a small raised area used to help define the traffic flow, and which may also act as a refuge for pedestrians crossing the carriageway or a location for signs, barriers or lights. A synonym for roundabout in some parts of the UK.

Median – on divided roads, including expressways, motorways, or autobahns, the central reservation (British English), median (North American English), median strip (North American English and Australian English, neutral ground or central nature strip (Australian English) is the area which separates opposing lanes of traffic.

Mountain pass – lower point that allows easier access through a range of mountains.

Milestone – one of a series of numbered markers placed along a road at regular intervals, showing the distance to destinations.

National Highway – road built and maintained by a national authority. Pedestrian crossing – designated point on a road at which some means are employed to assist pedestrians wishing to cross safely.

Private highway – highway owned and operated for profit by private industry. Private road – road owned and maintained by a private individual, organization, or company rather than by a government.

Public space – place where anyone has a right to come without being excluded because of economic or social conditions.

Pullout (layby, pull-off) – a paved area beside a main road where cars can stop temporarily to let another car pass.

Ranch road – U.S. road which serves to connect rural and agricultural areas to market towns.

Road number – often assigned to a stretch of public roadway. The number chosen is often dependent on the type of road, with numbers differentiating between interstates, motorways, arterial thoroughfares, and so forth.

Roughness – deviations from a true planar pavement surface, which affects vehicle suspension deflection, dynamic loading, ride quality, surface drainage and winter operations. Roughness has wavelengths ranging from 500 mm up to some 40 m. The upper limit may be as high as 350 m when considering motion sickness aspects; motion sickness is generated by motion with down to 0.1 Hz frequency.

Roundabout – in the UK a road junction where typically three or more roads are joined by a circular section of road. Traffic “on the roundabout” has priority over traffic on approach roads, unless indicated otherwise. In countries where traffic drives on the left the roundabout is travelled in a clockwise direction.

State highway – road numbered by the state, falling below numbered national highways (like U.S. Routes) in the hierarchy, or a road maintained by the state, including nationally-numbered highways.

10. Read the text and divide it into five parts, corresponding to the following titles:

1)On classification procedure and process

2)Basic concept

3)Purposes of functional classification

4)Use of more detailed functional class breakdowns

5)Access and mobility

FUNCTIONAL CLASSIFICATION OF ROADS

Countries manage their road systems by administrative and functional classifications. The former assigns road ownership, the latter presides over technical requirements and maintenance practices, and influence the administrative classification and financing. In many countries these two classifications are gradually approaching each other, although they never can fully coincide.

Functional classification is an indispensable tool for rational assessment and assignment of responsibilities in the road sector. For numerous reasons, including transferability of benchmarks and comparison of performance indicators, it would be beneficial if it used common criteria.

For administration countries have organized their roads into hierarchical networks according to their main purposes, i.e. national roads for roads linking the capital to provincial centers, principal cities and other centers of national importance; urban roads for roads and streets serving transport demands within cities and towns; and, rural roads for local transport demands in rural areas. Already the Romans knew that this was not enough and classified roads also functionally, which has evolved into a modern practice. Functional classification is the process by which the roads are grouped into classes by the service they are intended to provide. Basic to this process is the recognition that a trip involves movement through a network of roads. Functionally classified road network

assigns each road link a role that channels trips through a network efficiently. Allied to the idea of channeling traffic is the dual role the road network

plays in providing access to property and in travel mobility. Access is a fixed requirement, necessary at both ends of any trip. Mobility along the path of such trips is defined in terms of “level of service”. It can incorporate a wide range of indicators: road condition, travel speed, degree of congestion, and so forth.

The concept of channeling traffic leads not only to a functional hierarchy, but also to an hierarchy of trip distances. Local roads, for example, emphasize the land access function and arterials emphasize the mobility function; collectors offer a compromise between both functions. Consequently, arterials should have the highest traffic volumes, the greatest amount of commercial traffic, and the longest average trip lengths. Collectors should have intermediate values for these factors, and locals the lowest values. Also, the longest trips should have the highest percentage of their trips on arterials, and the shortest trips should be concentrated on locals.

The most important purposes and uses of functional classification include:

delineation of public responsibilities in the provision and standard of public roads;

assignment of a road’s ownership and responsibility for its management and financing;

system planning for the road using travel modes, including non-motorized traffic; access management (access control); and, coordination with other modes of transport;

assistance to road users for selecting a travel route from origin to destination;

assignment of (uniform) minimum standards, including permissible vehicle axle loads, weights and dimensions;

determination of the size of the public road network and its quality commensurate with what the country can afford at the time.

It is important for any classification or re-classification study to invite, with an introduction to the subject, the participation of all stakeholders in the exercise to express their interests and concerns.

Concurrent technical work should consider the population and the location of centers for administration, social and economic activities such as education and health, commerce and trade, manufacturing, private and public services, and important transport junctions such as ports, rail stations and border crossings. Following a description of the various centers they may then be divided into groups by their importance at national, regional, provincial, and district level.

The adoption of minimum standards for each class of roads will have financial implications. It is important that the standards adopted are linked to current road standards and what the country can afford at the time. The advantages of this include standardization of services across regions, and an implicit requirement that requests for upgrading will have to be justified by

savings in travel and transport costs. Road classification exercise needs to be carried out with a view to the governments’ financial capacity and users’ willingness to pay for roads. A road network which is too large or has too high technical standards will deteriorate. For roads which are only of limited public interest, the government or local authority may only offer a contribution towards their maintenance provided the users maintain them at their expense (normally at lower standard and also allow limited public travel).

Functional classification is a permanent but evolving representation of the road network. Demand for road access changes with economic growth and increasing prosperity, with relocation of population, economic activities and trade routes, and with expansion of urban areas and concerns for the environment. The functional classification must thus be updated periodically to take account of changes in transport demands and the road network to fulfill its role as a management tool.

For several reasons, a state or country may wish to create more than the three functional classes. One reason may be that there are more than three levels of road owners with road system responsibilities. Another reason for creating additional classes is to distinguish that portion of the road system for which the highest design standards (e.g., motorways) are warranted from other arterials that are under the jurisdiction of state or national governments, but which do not warrant.

An important and difficult aspect of the classification exercise is to establish how far the government can afford to go in assuming responsibility for basic access, in particular in rural areas. A large part of the road network in Finland and Sweden is owned and maintained by private cooperatives with some financial assistance from the government and local authorities. Equally important are the minimum technical standards. In rural areas, are all-weather 2- lane earth roads affordable and acceptable; or are one-lane roads more appropriate? The financial trade off between network extension and minimum standard is an issue to be considered carefully.

Finally, specialized functional classes may be desirable in some states or countries because of unique functions served. Examples include parkways, truck routes, busways and high occupancy vehicle routes, private (access) roads and routes for non-motorized vehicles.

The following list offers this more extensive classification system. The names are descriptive and countries often have their own names for classes. Again it would be useful if the criteria for classifying roads and paths functionally were the same regardless what the naming system a country has.

11.Say which of these statements are true or false. If the statement is false explain why.

1)Administrative classification of roads presides over road ownerships.

2)In many countries administrative and functional classifications are considered to be the same things.

3)One of the main goals of functional classification is rational assessment and assignment of responsibilities in the road sector.

4)According to functional classification all of the roads have been organized into three groups: national, urban and rural roads.

5)Mobility can incorporate a wide range of indicators: road condition, travel speed, degree of congestion, and so forth.

6)Arterials should have the highest traffic volumes because they emphasize the land access function.

7)Such information as the location of centers for administration, social and economic activities and important transport junctions and border crossings should be considered according to functional classification.

8)All type of roads are maintained at government’s expense.

12.Answer the following questions using the information from the

text:

1)What are the most important purposes and applications of functional classification?

2)What points should be kept in mind for any classification or re-classification study?

3)Why does the road classification exercise need to be carried out not only with a view to the governments’ financial capacity but it should take into account users’ willingness to pay for roads?

4)Should the functional classification be updated periodically? If yes, why?

5)What are the main functions of such types of roads as locals, arterials, collectors and motorways?

6)Are functional classes of roads common for every country?

7)Is it important that the criteria for classifying roads and paths functionally will be the same regardless what the naming system a country has?

13.Find these word combinations in the text, translate them and make a brief rendering of the text using them:

administrative and functional classifications, fully coincide, rational assessment, hierarchical networks, channeling traffic, delineation of public responsibilities, transport junctions and border crossing, current road standards, trip distances, implicit requirement, financial capacity, offer a contribution, assume responsibility for, financial trade off, network extension.