In this article we will discuss about:- 1. Definition of Highway Capacity 2. Importance of the Concept of Highway Capacity 3. Factors Affecting Capacity and Level of Service 4. Traffic Capacity Formula. Definition of Highway Capacity: Highway capacity is associated with traffic volume and traffic density. Traffic volume is the number of vehicles passing a given point on a roadway [...]
Traffic Signals: Notes, Importance and Methods Used for the design of traffic signals. The following definitions, concepts and explanations are useful or important in and relevant to the design of traffic signals. (i) Time Cycle: The period of time required for the complete sequence of signal aspect at any one arm of an intersection from red to the onset of [...]
A rotary intersection is a specialised form of intersection-at-grade in which the traffic movies in one direction round a central island. For 'keep-to-the-left' rule, vehicles approaching the intersection are forced to move around the central island in an orderly manner and weave out of the rotary into their respective desired directions. Design Elements of a Rotary: A number of elements [...]
A good highway network provides several benefits to the general public and the society at large. However, any new highway project, or improvements to an existing highway for meeting increased traffic demands should be justified from the economic point of view. That is to say, an analysis of the economic cost - the initial cost and maintenance cost over the [...]
Highway economic analysis, also known as highway project appraisal, involves quantification of the costs of and benefits from a scheme over a selected time horizon and evaluation by a common yardstick. The technique is also known as benefit-cost analysis. Such economic evaluation serves a number of purposes: (i) To rank different schemes within the highway sector. (ii) To assist in [...]
In this article we will discuss about how to design plain jointed rigid pavements for highways by IRC Method. IRC Method of Rigid Pavement Design: This method is based on mechanistic-empirical principles and the use of software IITRIGID for the computation of flexural stresses due to single and tandem axle loads. The design of a rigid pavement consists of: (i) [...]
Concrete Roads: PQC, Methods of Construction and How it is Made! Introduction to Concrete Roads: Concrete roads fall under the category of high quality/superior type of roads built with cement concrete. These pavements may or may not be provided with sub-base/base courses, and they may be constructed directly over a well-compacted soil subgrade. They derive their strength to support the [...]
In this article we will discuss about how to stabilise soil for road construction. Learn about:- 1. Mechanical Stabilization 2. Stabilisation with Additives. 1. Mechanical Stabilization: Rearrangement of the soil grains and densification by compaction is the first approach. The other approach consists of blending two or more available soils to obtain the desired gradation of soil particles for the [...]
Highway Drainage: Need and Types of Highway Drainage System! Highway drainage consists of removing or controlling surface water and subsurface water away from the road surface and the subgrade supporting it. Part of the rain water flows on the ground or road surface, while the other part percolates into the ground and reaches the ground water table, raising its level. [...]
In this article we will discuss about:- 1. Alignment of Hill Roads 2. Geometric Design Aspects of Hill Roads 3. Maintenance Aspects. Alignment of Hill Roads: 1. Administrative, developmental and strategic needs would determine the obligatory points to be connected by a hill road. Control points would be governed by saddles, passes, river crossings, and other natural features such as [...]