Unit-1

Introduction

Q1) What are the different modes of transportation? Explain the specific function of each of them.

A1) There are five modes of transportation.

Road transport exists in all parts of the world, this involves the use of motor vehicles (cars, lorries, buses, bicycles, and trucks). There are various types of roads according to size and functions, some roads are tarred while others are not. The best of these roads are the modern roads which link major towns. Road transport, when compared with other modes of transportation, is more flexible. It is relatively cheaper and faster. Road transport has a high capacity for carrying goods over short distances. Maintenance is one of the major disadvantages of this mode of transport.

Railways were developed during the period of the industrial revolution in the 19th century; these were partly for political reasons and for economic reasons. In many countries, they were built specially to penetrate isolated regions and help promote political unity. The major advantage of railway transport includes the provision of reliable services. It has the ability to convey heavy and bulky goods; it is also very cheap, safe, and also comfortable for passengers over a long distance.

Water transport is very important because it is the cheapest way of transporting bulky goods over a long distance.

In the world, there are two major types of water transport namely: Inland water transport and ocean water transport.

      Inland water transport

This is the system of transport through all navigable rivers, lakes, and man-made canals.

However, Ocean waterways carry a lot of the world’s trade, the majority of the bulky goods, materials, and passengers pass through ocean waterways from one country to another at the cheapest cost.

Air transport is the newest means of transport; it was introduced in 1903 but developed into full means of transporting people and goods in the 1930s. The greatest air transportation started after the Second World War (WWII). This mode of transportation can be used for both domestic and international flights.

This system of transportation involves the use of hollow pipes in the transportation of water, crude oil, (petroleum) and gas. This mode of transportation is safer than using tankers or trailers in the transportation of these liquids.

Q2) Explain the role of transportation in rural development of India?

A2) Transport is very essential for the development of rural areas. It can be explained in the following ways:

Q3) Calculate the lengths of National and State highways required in a district with a total area of 7200 km2, developed, semi-developed and undeveloped areas being 30, 45, and 25% of the district. The number of towns with population over 1.0, 0.5-1.0, 0.2-0.5 and 0.2-0.2 lakhs are 3, 7, 12 and 20 respectively. Use the formula:

               NH = (A/64 + B/80 + C/96 + 32 k + 8M) + D

     NH + SH = (A/20 + B/24 + C/32 + 48K + 24M + 11.2N + 1.6P) + D

A3)

 A = 7200 X 0.30 = 2160 km2

B = 7200 X 0.45 = 3240 km2

 C = 7200 X 0.25 = 1800 km2

 K = 3

  M = 7

 N =12

   P = 20

  D = 5% of road length

NH = ( + + + 32 X 3 + 8 X 7) + 5% of RL

      = 245 X 10.5 = 257.25 km

NH + SH = ( + + + 48 X 3 + 24 X 7 + 11.2 X 12 + 1.6 X 20) + 5% of RL

    = 777.65 X 10.5 = 816.53 km

SH = 816.53 – 257.25 = 559.28 km

Q4) Explain outline the highway development in India.

A4) The road development in India can be discussed by taking different phases of history at one time, as follows.

Ancient Times

The excavation of the Mohn-Jodaro and Harappa civilization shows the traces of the roads in the ancient Indian times, in a period f 35th to 25th B.C. 

The Aryan Period and Road Construction

There are various scriptures available, which script about road development in India in the Aryan period. “Arthashastra” written by Kautilya (Chanakya), the prime minister of the Chandra Gupta Mourya, discusses the rules laid down for the depth of the road construction for different purposes in the 4th century.

Mughal period and Road Construction

The Mughal and Pathans improved the quality of the roads in India. Sher Shah Suri is still remembered for the construction of the Grand Trunk Road (GT Road) from Bangladesh-India to Kabul, in Afghanistan.

19th Century and Road Construction in India

After the fall of the Mughal Empire in India in the 19th century, the Britishers participated in the road construction for the military and administrative purposes. 

The work was carried out by the British Military Engineers. The railway was introduced later but the existing roads were metaled and bridges were provided. The governor-general of India i.e. Lord Dalhousie in the mid of 19th century introduced the PWD (Public works department), which still runs the various public works in India. Later after the introduction of the railways in India, the attention was shifted to the railways’ construction and only the feeder roads and railways got the prime importance afterwards.

Jayakar

The committee was formed by both chambers of the Indian Legislature in the year 1927 to examine the roads in India and ways of their development. The number of vehicles on the Indian roads increased after the First World War, so it was felt necessary to develop a good network of the roads in India.

 

Indian Road Development Committee was formed in the year 1927, with M.R.Jayakar as its chairman. The committee submitted its report in the year 1928, and made some important recommendations:

The road development in India should be considered a national interest because it is out of control of the local bodies. 

As a result of these recommendations, a central Road Fund was formed by the year 1929, a semi-official body called Indian Roads Congress was formed in 1934 and the Central Roads Research Institute was started in 1950.

Central Road Fund (1929)

Central Road Fund was formed in the year 1929, extra money 2.64 Paisa per litre of petrol, was charged from the entire petrol buyer in the country. This fund was kept separate for the use in the road development in India.

About 20% of the fund was kept to be used for the expenses of the administrative meetings and the research work of the highways of the national importance in the country. The rest of the 80% of the funds were distributed among the provinces at that time, according to their road users, for the development of the roads by the state governments.

Indian Roads Congress (1934)

A semi-government organization named, Indian Roads Congress was formed in the year December 1934 and was registered in the year 1937 under the registration act.

 The main function of the IRC was to act as a forum for the regular pooling of the technical knowledge and know-how, from the various parts of the country.

Q5) What are the various surveys to be carried out before planning a highway system for a given area? Explain briefly.

A5) We have to locate an alignment which fulfils the basic requirements like the path must be short, safe, economic, easy and useful.

Engineering Surveys in the following phases:

Map Study

This is the first step of the Engineering survey, using a topographic map of the area under consideration, which can be availed from the Survey of India. 
This topographic map, in general, has a contour interval of around 30 m to 40 m.

Reconnaissance Survey

So in the second phase/step a survey team is headed to the area under study with the minor surveying instruments like Abney level, Tangent Clinometers etc. to do a rough survey of the area under study. 

The rough survey is done along the alternatives proposed in the map study and feasibility of the road alignment is checked along the different routes. 

Some of the routes may be cancelled out or they may be changed if they appear to be impossible in this study. So finally they will have a set of routes which are to be further studies in the next step.

Preliminary Survey

In this step, the alternative routes which are proposed after a rough survey in the second step are surveyed in details using some advanced instruments like levels, chain and theodolite. Aerial Photogrammetry is best suited for this type of survey.
All the necessary details to carry out the comparative study of the different routes are collected and then finally we have to decide one alignment best suited for the alignment of the road. 

Here various details are found out along the stretches of the routes, which can also be found using the aerial techniques by taking photographs along the routes and then further processed to find out the final details of the area.    

 Location Survey

 Location of the centerline of the road is done with very much precise instrument like Theodolite and Chain using the drawing prepared or the details gathered in the third step (i.e. Preliminary survey). This is done by staking the ground with the stakes inserted at the intervals of 50 m to 100 m in the plain area, 50 m to 75 m in the rolling terrain and 30 m to 50 m in the hills and steep terrain.   

Pegs may be driven at all the control points. At the curves control points, starting of the transition curve, starting off the circular curve and terminal of the circular curve and the terminal of the transition curve the pegs/stakes are driven into the ground to firmly locate these control points. Benchmarks are located at an interval of 250 m and they are necessarily located at the sites of the cross drainage works.

Detailed Survey

In this part, we have carried out the detailed study of the final route using some very precise instruments like Theodolite and Chain to gather all the necessary data for the final estimation, design and preparing drawings using which the construction can be started. A detailed project report is to be prepared and all the necessary data is collected to prepare that report.

 So, the profiling, cross-sectioning and soil investigation are carried out very precisely. CBR values are also found to find out the design thickness of the pavement. After collecting the data a final drawing a report is prepared which concludes the highway planning part. 

Q6) Discuss the second twenty-year road plan of 1961-81 and its salient features.

A6) The length of roads was under the Nagpur plan was achieved by the end of it, but the road system was deficient in many respects. Accordingly, a 20 year plan was drafted by the roads wing of government of India, which is popularly known as the Bombay plan. The highlight of the plan was

●      It was the second-year road plan 1961 to 1981.

●      The total road length targeted to construct was about 10 lakhs.

●      They suggested that the length of the rod should be increased so as to give a road density of 32 km per hundred square kilometers.

Q7) What are the significant recommendations of Jayakar Committee Report?

A7)

6.     IRC played an important role in the formation of the three 20-year road development plans in India:

Q8) Explain the various factors controlling the alignments of roads.

A8)

Obligatory points

These are formed control points governing the highway alignment full stop these points are classified into two categories. Point’s pass through which it should pass and points through which it should not pass. Some of the examples are

      Bridge site

The bridge can be located only where the river has straight and permanent path and also where the abutment and pier can be strongly founded. The road approach to the bridge should not be curved and skew crossing should be avoided as possible.     

      Mountain

Why the alignment passes through a mountain, the various alternatives are to either construct a tunnel or to go around the hills. The suitability of the alternative depends on factors like topography, site conditions and construction and operation cost.

      Intermediate town

The alignment may be slightly divided to connect an intermediate town or village nearby.

Second category that is the points through which all the alignments should not pass are

      Religious places

These have been protected by the law from being acquired for any purpose. Therefore, this point should be avoided while alleging.

      Very costly structures

Acquiring such structures means heavy compensation which would result is an increase in initial cost. So the alignment may be debited not to pass through that point.

      Lakes or ponds

The presence of a lake or pond on the alignment paath would also necessitate deviation of the alignment.

      Traffic

The alignment should suit the traffic requirements. Based on the origin destination data of the area, the desire line should be drawn. The new alignment should be drawn keeping in view the desire line and traffic flow patterns etc.

      Geometric design

Geometric design factors such as gradient, radius of curve, sight distance etc. also governs the alignment of the highway. To keep the radius of curve minimum, it may be required to change the alignment of the highway.  The alignment should be finalized such that the obstruction to visibility does not restrict the minimum requirements of sight distance. The design standards vary with the class of roads and the terrain and accordingly the highway should be aligned.

Q9) Explain briefly the various stages of work in a new Highway project.

A9)

Road construction is a lengthy process that can take more than 10 years, depending on the size of the future pathway. It involves several construction crews and plant machinery and requires careful planning and various evaluations, including environmental and structural assessments.

Clearing and Excavation

The area on which the road is going to be built on must be cleared of all vegetation, which requires the removal of trees, shrubs and bushes. Excavation vehicles will also dig up and remove rocks and stones from the future road's pathway. To prevent the cleared land from erosion, control devices, including fences, ditches and basins are installed.

Mounting

The road takes shape as diggers, excavation plant machinery and bulldozers mount dirt and soil over the area where the future pathway will run. The surface is then leveled and smoothed by graders. Culverts and drains, consisting of large concrete pipes, are laid to prevent the road from flooding by leading away groundwater, sewage or storm water.

Fine Grading

Fine grading requires construction workers to prepare the surface by leveling it according to plans provided by structural engineers. Fine grading requires manual labour and digging as well as grading plant machinery, also called graders. To make the grading last, it is stabilized with limestone or concrete.

Aggregate Base

After another grading of the surface, the aggregate base course is laid. Aggregate base is made of crushed stone or gravel, and it is placed evenly on the road surface. If the road is in a town or city, a curb for the pavement and the gutter will be constructed straight after the gravel is placed on the surface. The road is then fine graded again.

Asphalt Paving

Once the gravel has been distributed evenly, the asphalt can be poured. Asphalt is a mixture of a petroleum byproduct, an aggregate base material and a sticky, gluelike substance called bitumen. Depending on the expected traffic on the road, up to four layers of asphalt can be placed on top of each other. The asphalt usually is produced and mixed in large plants after the engineer's specifications. The hot asphalt is filled into trucks that transport the material to the construction site where it will be poured immediately. Before the last layer of asphalt is poured, the sidewalks and gutters have to be finished. The construction work is concluded by placing the appropriate road signs at the places specified by planners and the application of road markings.

Q10) What are the various types of roads and its pattern?

A10)

Primary, secondary & tertiary road system

      Primary: Expressways & National Highways (NH)

      Secondary: State Highways (SH) & Major District Roads (MDR)

      Tertiary: Other District Roads (ODR) & Village Roads (VR)

On the basis of usage during different seasons

      All-weather Roads: negotiable during all weathers

      Fair-weather Roads: negotiable during all weathers except monsoon season where streams may overflow across the road

On the basis of road pavement

      Paved Roads: provided with hard pavement surface which should be at least a Water Bound Macadam

      Unpaved Roads: earth roads and gravel roads

On the basis of pavement surfacing

      Surface Roads: provided with bituminous or cement concrete surfacing

      Un-surfaced Roads: not provided with bituminous or cement concrete surfacing

Classification of rural & urban roads

Rural Roads: classified on the following basis –

a)     Traffic Volume – Heavy, medium or light

b)    Load Transport – Class A, Class B etc

c)     Location & Function

Urban Roads: classified into the following types –

a)     Arterial Roads

b)    Sub-arterial Roads

c)     Collector Streets

d)    Local Streets

Road pattern

Rectangular/ Block / Grid pattern

The rectangular/ block/ grid pattern is a plan where the streets and roads are in the form of grids or blocks running perpendicularly into each other thus forming a grid or block. The North Nazimabad area of Karachi in Pakistan is a factual example of this type of pattern where the streets and roads run at an angle of ninety degree into each other. Usually in this type of pattern the streets and roads are far away from each other and it takes a long time to reach the center of the area or city.

Radial Pattern

This type of network is a combination of radial and block pattern. A radial network of roads radiates from the centre outwardly with block pattern network of roads in between the radial main streets. In this pattern, the entire area is divided into a network of roads radiating from the business outwardly. In between radiating main roads, the built-up area may be planned with rectangular block.

Radial or star and circular pattern

In this system, the main radial roads radiating from central business area are connected together with concentric roads. In these areas, boundary by adjacent radial roads and corresponding circular roads, the built-up area is planned with a curved block system.

Advantages:

1)At traditional intersections with stop signs or traffic signals, some of the most common types of crashes are right-angle, left-turn, and head-on collisions. These types of collisions can be severe because vehicles may be traveling through the intersection at high speeds. With circular pattern, these types of potentially serious crashes essentially are eliminated because vehicles travel in the same direction.

2) Installing circular pattern in place of traffic signals can also reduce the likelihood of rear-end crashes.

Hexagonal Pattern

This pattern is a network of roads that grow in such a manner in various directions forming hexagons. In this pattern the entire area is provided with a network of roads formatting hexagonal figures. At each corner of the hexagon, three roads meet the built up area boundary by the sides of hexagons is further divided in suitable sizes.