LESSON 2 (Updated).pdf

HIGHWAY DEVELOPMENT AND PLANNING WHAT IS A HIGHWAY? - A highway is considered a conduit that carries vehicular traffic from one location to another. WHAT IS HIGHWAY ENGINEERING? - Highway engineering deals with provisions for meeting public needs for highways; environmental impac...

HIGHWAY DEVELOPMENT AND PLANNING WHAT IS A HIGHWAY? - A highway is considered a conduit that carries vehicular traffic from one location to another. WHAT IS HIGHWAY ENGINEERING? - Highway engineering deals with provisions for meeting public needs for highways; environmental impact of highways; budgeting, planning, design, construction, maintenance, and rehabilitation of highways; access to and exit from highways; economic and financing of highway construction; traffic control; and safety of those using or affected by the use of highways. BRIEF HISTORY The first mode of transport was by foot. These human pathways would have been developed for specific purposes leading to camp sites, food, streams for drinking water etc. The next major mode of transport was the use of animals/pack animals, crude sleds were developed for transporting both men and materials. The invention of wheel in Mesopotamian civilization led to the development of animal drawn vehicles. Then it became necessary that the road surface should be capable of carrying greater loads. After the invention of wheel, animal drawn vehicles were developed and the need for hard surface road emerged. Traces of such hard roads were obtained from various ancient civilization dated as old as 3500 BC. The earliest authentic record of road was found from Assyrian empire constructed about 1900 BC. Another stone surface roads were also found in the Mediterranean island of Crete, similarly constructed as those in the Western Hemisphere by the Mayans, Aztecs and the Incas of Central South America. The earliest large-scale road construction is attributed to Romans who constructed an extensive system of roads radiating in many directions from Rome. Their roads were very durable, and some are still existing after more than 2000 years. The next major development in the road construction occurred during the regime of Napoleon. The significant contributions were given by Jerome Tresaguet (1716-1796) the famous French engineer who introduce new methods of construction and maintenance of stone roads in 1764 and a typical cross section of this road is given in Figure 2:2. He developed a cheaper method of construction. He also improved the crown, the drainage, and the grade of the road, including the stone foundation by reducing the depth of broken stones to 25 mm.  Thirty years later, a Scottish Engineer born in Westminster Abbey, Thomas Telford (1757- 1834), president and founder of the Institute of Civil Engineer, introduced some improvements in the construction methods of Jerome Tresaguet. The road foundation course of Telford was made of stones having 3 inches minimum thickness, 5 inches breadth and 7 inches height. Smaller stones were driven by mauls on top voids and trued the surfaces by breaking the projecting points. Telford employed a flat sub-grade, providing slight crown using stones of varying sizes. England followed the ongoing highway development started by France. It was another Scottish engineer, John Loudon McAdam, who designed the first modern roads. He developed an inexpensive paving material of soil and stone aggregate (known as macadam). His road building method was simpler than Telford's, yet more effective at protecting roadways: he discovered that massive foundations of rock upon rock were unnecessary, and asserted that native soil alone would support the road and traffic upon it, as long as it was covered by a road crust that would protect the soil underneath from water and wear. The modern roads by and large follow Macadam’s construction method. o Use of bituminous concrete and cement concrete are the most important developments. o Various advanced and cost-effective construction technologies are used. Development of new equipment help in the faster construction of roads. o Many easily and locally available materials are tested in the laboratories and then implemented on roads for making economical and durable pavements. HIGHWAY DEVELOPMENT IN THE PHILIPPINES In the early part of 1900, transportations in the country depended largely on trails, waterways, railroads, earth roads and partially graveled roads. Highways in the Philippines at that time is nothing more than a dream to most Filipinos. The American government initiated the development of roadways in the Philippines connecting towns, cities and provinces. The popular Macadam Road types was introduced. It gained wide acceptance because of the abundant supply of stones and gravel. After the Second World War, the new Independent Philippine government, continued the rehabilitation and construction of roads and bridges, through the reparations and war damages paid by the Japanese government. Other financial grants and aids received from the U.S. government were used in the construction and rehabilitation of roads and bridges. Fifty years later, major highways and expressways were constructed through the financial assistance and loans from foreign banks. The year 1960 to early part of 1980 was considered an automobile age. Cars were no longer regarded as luxury item but a necessity in transporting people and goods, a necessity for survival. Government new concept of development is to get the farmers out of the mud. It was during this decade that road construction becomes a matter of priority of the government under the slogan. "This Nation is on Wheels". WHY ARE HIGHWAYS SO IMPORTANT? - Highways are vitally important to a country’s economic development. The construction of a high- quality road network directly increases a nation’s economic output by reducing journey times and costs, making a region more attractive economically. HIGHWAY PLANNING Highway planning is a basic need for highway development. Objective of Highway Planning: To plan a road network for efficient and safe traffic operation, but at a minimum cost. The cost of construction, maintenance and renewal of pavement layers and the vehicle operation coast are given due consideration. To arrive at the road system and gthe lengths of different categories of roads which could provide maximum utility and could be constructed within the available resources during the plan period under consideration. To fix up date wise priorities for development of each road link based on utility as main criterion for phasing the road development programmed. To plan for future requirements and improvement of roads in view of the anticipated developments. To work out financing systems. HIGHWAY PROGRAMMING Three inseparable sets of inputs 1. Economic – deals with the questions of resources. 2. Financial – the question of who pays and who spends, how much and where? 3. Political and Administration – this involves decision making. HIGHWAY PROGRAMMING APPROACHES 1. Financial resources are either short or long ranged implementation by the agency’s functions like construction, operations, and maintenance. 2. Recognition of the legislative and administrative desire and constraint. 3. Tentative priorities based on economic analysis, critical situations, present and future expected level of traffic, and claims based on political subdivisions. 4. Providing continuity of route system and coordination with other transportation mode. 5. Selection of projects based on availability of labor and materials, including climatic conditions. 6. Scheduling the project implementation in coordination with other agencies, acquiring right of way and making final plan and specifications. 7. Budgetary reserve to cover emergencies like floods and other natural disasters. CLASSIFICATION OF ROADS The roads can be classified into: 1. Functional - based on speed and accessibility 2. Jurisdictional - Road is classified with respect to the entity (private, municipal, state, or federal) responsible for their construction, maintenance, and operation. The roads can be classified as follows in the order of increased accessibility and reduced speeds. Freeways - A freeway is a divided highway with fully controlled access. - Access to a freeway is made without use of at-grade intersections. - Most freeways are four lanes, two lanes each direction, but many freeways widen to incorporate more lanes as they enter urban areas. - Access is controlled through the use of interchanges, and the type of interchange depends upon the kind of intersecting road way (rural roads, another freeway etc.) Expressways - They are superior type of highways and are designed for high speeds (120 km/hr is common), high traffic volume and safety. - They are generally provided with grade separations at intersections. - Parking, loading and unloading of goods and pedestrian traffic is not allowed on expressways. Arterials - Arterials are highways that provide direct service to major population centers. - It is a general term denoting a street primarily meant for through traffic usually on a continuous route. - They are generally divided highways with fully or partially controlled access. Parking, loading and unloading activities are usually restricted and regulated. - Pedestrians are allowed to cross only at intersections/designated pedestrian crossings. (Schematic of a rural highway network serving towns, villages, and cities.) Local streets - Local roads connect various regions of a municipality and tie into the system of collectors. - A local street is the one which is primarily intended for access to residence, business or abutting property. - It does not normally carry large volume of traffic and also it allows unrestricted parking and pedestrian movements. Collector streets - Collectors provide direct service to towns and link up with arterials. - These are streets intended for collecting and distributing traffic to and from local streets and also for providing access to arterial streets. - Normally full access is provided on these streets. - There are few parking restrictions except during peak hours. Philippine Road Classification By virtue of Executive Order No. 180, series of 1948 signed by then Philippine President Elpidio Quirino Road classification in the Philippines were the following: National Highway Main traffic routes connecting provincial capitals with important commercial centers, national airports, national seaports, and national parks and roads of military importance, which may be  so designated by the President, upon favorable recommendation of the Secretary of Public Works and Communications. Today national highway is further classified into three types by the Department of Public Works and Highways under the Philippine Highway Act (Republic Act No. 917) signed by President Elpidio Quirino on June 20, 1953 and the series of memorandums issued by the Department between 2009 and 2014. They are the national primary roads, national secondary and national tertiary road. Provincial Roads Connect Cities and Municipalities without traversing National Roads. Connect National Roads to Barangays through rural areas. All roads connecting one municipality with another municipality the terminal to be the public plazas; all roads extending from a municipality, or from a provincial or national road to a public wharf or railway station and any other road which may be so designated by the Secretary of Public Works and Communications upon the request of the Provincial Board concerned and upon favorable recommendation of the Director of Public Works. Municipal and City Roads Roads within the Población Roads that connect to Provincial and National Roads Roads that provide inter-Barangay connections to major Municipal and City Infrastructure without traversing Provincial Roads ROAD PATTERNS Roadway patterns are very essential in the development of the settlements of a city (Jamal, 2017). If it is not integrated in the design and development of road networks in the city it will cause to numerous roads that are not interconnected. Therefore, it will cause increased travel distance and dependency on car for the people to do their daily chores. On the other hand, highway development that integrated road patterns make it easier for people to reach their destination. TYPES OF ROAD PATTERNS Rectangular - This is also called grid or block pattern. In this pattern, the whole area is divided into grids or blocks running perpendicularly into each other. An example of this is in Makati City and other parts of Metro Manila. The advantage for this pattern is that this pattern is sufficiently easier to construct and maintain. This type of street pattern has a good aesthetic view and the road geometry is easier to understand. But this pattern in terms of safety is not convenient because at the intersections, the vehicles face each other at opposite directions. Radial the area is divided into network of roads in the form of a circle or ellipse and from the center, roads emanate forming like a star. Divides further into three patterns. o Star Block Pattern o Star Circular Pattern o Star Grid Pattern The advantage of this type is that it reduces the possibility of congestion at the roundabouts because the traffic can effortlessly join. Hexagonal Pattern 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 the hexagons is further divided in suitable sizes. Travel time and distance are kept to a minimum. Minimum Travel Pattern The town is satisfied by sector centers, suburban facilities, and neighborhood centers, all of which are connected to the city center by a highway that takes the shortest time to reach. Also, the shortest roads interconnect the city center with neighboring and suburban centers. The alignment of the road is made straight to shorten it.