History of Road development

 Early Development

 The oldest mode of travel obviously was on the foot-paths. Animals were also used to transport men and materials. Later simple animal-drawn vehicles were developed and this became a common and popular mode of transportation for a very long period after the invention of the wheel. This brought up the necessity of providing a hard surface for these wheeled vehicles to move on. Such a hard surface is believed to have existed in Mesopotamia in the period about 3500 BC the first road on which there is authentic record is that of the American empire constructed by about 1900 BC Only during the period of the Roman Empire, roads were constructed in large scale and the earliest construction techniques are known of Roman Roads the Romans constructed an extensive system of roads radiating in many directions from Rome through the empire mainly for military operations. Hence Romans are considered to be the pioneers in real construction.

 

Roman Roads

 

Many of the early Roman roads were of elaborate construction. Some of these roles are still in existence after over 2000 years. During this period of Roman civilization, many

roads were built of stone blocks of considerable thickness The Appian way was built in 312

B.C. extending over 580 km which illustrates the road-building technique wed by Romans.

 

The main features of the Romans roads are:

(i) They were built straight regardless of gradients.

(ii) They were built after the soft soil was removed and a hard stratum was reached.

(ii) The total thickness of the construction was as high as 0.75 to 1.2 meters at some places, even though the magnitude of wheel loads of animal-drawn vehicles was very low.

 

 Tresaguet Construction

 

After the fall of the Roman empire, their technique of road construction did not gain popularity in other countries. Until the eighteenth century, there is no evidence of any new road construction method, except the older concept of using thick construction of road beads as the Roman did. Pierre Tresaguet (1716-1796) developed an improved method of construction in France by the year 1964 A.D. Tresaguet developed several methods of construction which were considered to be quite meritorious. The main feature of his proposal was that the thickness of construction need be only in the order of 30 cm. consideration was given by him to subgrade moisture condition and drainage of surface Further due water. Tresaguet was the Inspector General of Roads in France from 1775 to 1785 and so his method of construction was implemented in that country in 1775. During the regime of Napoleon, the major development of the road system in France took place.

 

Metcalf Construction

 

John Metcalf (1717-1810) was engaged in road construction works in England during the period when Tresaguet was working in France. He apparently followed the recommendations of Robert Phillips whose paper was presented in Royal Society; Metcalf was responsible for the construction of about 290 km of road in the northern region of England. As Metcalf was blind, much of his work was not recorded.

 

Telford Construction

 

Thomas Telford (1757-1834) began his work in the early 19th century. He was the founder of the Institution of Civil Engineers in London. He also believed in using heavy foundation stones above the soil subgrade in order to keep the road foundation firm. He insisted on providing a definite cross slope for the top surface of the pavement by varying the thickness of foundation stones.

 

      Macadam Construction

 

John Macadam (1756-1836) put forward an entirely new method of road construction as compared to all the previous methods. The first attempt to improve the road condition was made by him in 1815. Macadam was the Surveyor-General of Roads in England and his new concept of road construction became known by the year 1827.

 

Further Developments

 

Macadams method of construction gained recognition as a scientific method of construction and hence was adopted by various countries with slight modifications. One of the most popular methods which are even now prevalent in many countries is the water found macadam (WBM) construction, known after Macadam's technique. In this method the broken stones of the base course and surface course, if any, are bound by the stone dust in presence of moisture and hence the name. WBM roads are in use in India both as a finished pavement surface for minor roads and as a good base course for superior pavements carrying heavy traffic. There are also bituminous construction methods which are known after Macadam. The methods adopted in our country include the bitumen-bound macadam and penetration macadam. The details of the construction methods have been given in the Chapter, 'Highway Construction'.

 

The water-bound macadam roads were considered to be one of the superior methods of construction until the fast-moving vehicles started using these roads. Dust is formed on the road surface during dry weather due to the crushing and abrading action of steel-tired animal- drawn vehicles. This dust is easily raised by fast-moving automobiles. Further, during monsoons, mud is formed and is churned again due to the movement of automobiles. Under the combined action of the mixed traffic and under adverse weather conditions the WBM roads could not last long. In order to minimize the dust nuisance, several dust palliatives including heavy oils and bituminous materials were tried with varying degrees of success,

 

The next development was the penetration and bituminous macadam roads and other types of surface dressing methods using bituminous materials. For better performance superior bituminous mixes like the bituminous carpet and bituminous concrete were also developed Inna scientific way.

 

The use of cement concrete for roads has been popular even prior to the use of bituminous mixes. The cement concrete roads could be designed to keep up the heaviest loads expected on the roads even in adverse soil and climatic conditions and to last for long service life. They are known to give a good and even riding surface. Due to the high initial cost involved in the construction of cement concrete road, it is not being extensively used in our country at present. As the main problem in developing countries like India is to have maximum road length at minimum cost, the only solution is to resort to the construction of low-cost roads and stage construction of roads. Hence the best utilization of locally available and the cheapest materials have to be made in road construction. In this respect, there is good scope for the use of soil stabilization and other low-cost pavement materials. There are several techniques of soil stabilization that have been explained in a later chapter of the book. The choice of the method of stabilization depends on several factors such as the soil type, availability of stabilizers, climatic conditions, the component of pavement which is being constructed, and the traffic.

 

 Highway Development in India

 

 Roads in Ancient India

              The action of Mohenjo-Daro and Harappa have revealed the existence of roads in India as early a25 to 35 centuries BC Old records reveal that in early periods the roads were considered indispensable for administrative and military purposes. The ancient scriptures refer to the ice of roads during the Aryan period in the fourth century BC Kautilya the first prime minister of Emperor Chandra Gupta Maurya, laid down the rules in the literary piece titled 'Arthasastra'. Rules have been mentioned about regulating the depth of roads for various purposes and for different kinds of traffic Men have been made regarding the punishment for obstructing roads in the beginning fifth AD. emperor Ashoka had improved the roads and the facilities for the travelers.

 

 

Roads in Mughal Period

 

During the Pathan and Mughal periods, the roads of India were greatly improved, some of the highways either built or maintained by Mughals received great appreciation from the foreign visitors who visited India during that periods. Roads were built running from North-West to the Eastern areas through the Gangetic plains. linking also the coastal and central parts.

 

Roads in Nineteenth Century

       At the beginning of British rule, the conditions of roads deteriorated. The economic and political this caused damage to a great extent in the maintenance of the road transportation the fall of the Mughal empire led therefore to the scant attention to the communication Prior to the introduction of railways, a number of trunk roads were metalled and bridges were provided. this was mainly done on the remains of old roads which exempted, under the supervision of the British Military Engineers In fact these roads connected important military and business centers.

 

Military maintenance was not quite adequate and in 1865 Lord Dalhousie, when he was Governor-General formed the Public Works Department in more or less the same form that exists today. The construction of the Grand Trunk Road was undertaken by this new department. Immediately with the development of railways. The attention of the Government was shifted from road development except for providing feeder roads and the railway was gaining privileges.