INTRODUCTION OF HIGHWAY

 Introduction of highway;

A highway is any public road or other way on land. It is useful major roadsbut also includes  other public roads and public traks; It is not an equivalentterm to freeway [motorway]

Terms Used In Highway

Super Elevation

In civil engineering cant is often referrd to as cross slope or camber. It helps rainwater drain from the road surface. along straight or gently curved section the middle of the roads is normally higher than the edges.This is called "normal crown" and help shed rainwater off the side of the road. During road works that involve lenth of temporary carriageway, the slope may be the opposite to normal- i.e.with the outer edge higher - which causes vehicles to lean towards oncoming traffic; in the UK this is indicatedon warning signs as' adverse camber.

CURVE: 

Curve may filful any or several of a number of fucation. They separate the road from the roadside and discourage drive from parking or driving on sidewalks and lawns they also provide structural support to the payment edge. Curve can be used to channel channel runoff water from rain or melted snow and ice into strom drains.

There is also an asthetic aspect, in that curve look formal and finished.

CAMBER: 

Camber is the transverse slope provide to the surface to drane off the rain water from the road surface it also called cross slope, on the staraintroad camber is provide by raising the centre of the carriage way with the respact to the edge thus torming a highest point or crown of the centre line of the carriage in set of raising centre.

GRADIENT;

Gradient the rate or rise or fall of road surface along it's lenth with respect to the horizontal it is longitudinal slope provide to the road surface along its length it is exprided us a ratioof 1 in * [1 units vertical to into horizontal ] and also exprided us a percentage.

CLASSIFICATION OF HIGHWAY

TYPE OF HIGHWAY ACCORDING TO LANE;

[A] Two-Lane Highway

[B] Four-Lane Highway

TYPE OF HIGHWAY ACCORDING TO MATERIAL;

[A] Rigid Pavement

[B] Flexible Pavement

PURPOSE OF HIGHWAY;

Reducing travel times relative to city or town streets, moden highway with limited access and grade separation create increased opprtunities for people to travel for business, trade or pleasure and also provide trade routes for goods.Modernhighway reduce commute and other travel time but additional road capacty can also create new inducate traffic demand.

In transport demand can be measured in number of journeys made 0 in total distance travelled across all journery[e.g. passenger-kilometerfor public transport or vehicle-kilometer of travel [VKT] for private transport. Supply is considered to be a measure of capacity. The price of the good [teavel] is measured useing the generalised cost of travel, which include both money and time expenditure.

MATERIAL USED IN HIGHWAY

CONCRETE;

Concrete; is a composite material composed of course aggergate bonded together with a fluid cement which hardens over time. Most concretes used are lime -based concretes such as portland cement concrete or concrete made with other hydraulic cements, such as cement fondu. However road surface are also a type of concrete, asphalt concrete, where the cements material is bitumen, and polymerconcretes are sometimes used where the cementing material is a ploymer.

ASPHALT ;

The primary use [70%] of asphalt\bitumen is in road construction where is used as the glue or binder mixed with aggregate particales to create asphalt concrete. Its other main use are for  bituminous waterprofing products inciuding production of roofing felt and for sealing flat roofs.

AGGERGATES;

We use the aggerates of different grade. IRC [INDIAN ROAD CONGRESS] has classfised the course aggaergates into 9 geade according to their size. For the construction of the WBM roads aggergates are used in the sub-base, base and surface course and so the aggergatesare dividedinto 3 greads according to their size; 

Grade 1; particles of size 90 mm to 40 mm.

Grade 2; particles of size 63mm to 40mm.

Grade 3; particles of size 50mm to 20mm.

BINDERS;

Binders, are the layers of material which are laid after the compaction of the aggregates and the screeing materials one after the another. Kankar dust or lime stone dust may be utilized if locally available. The binding material with plasticityindex value of 4% to 9% is used in surface course construction the plasticity index of binding course material shuld be less than 6% in the case of the WBM layers used as base course or sub-base course with bituminous surfacing. Howere if the screeing used are of crushabie material like moorum or shoft gravel, there is no need to apply binding material, unless the plasticty index value is low.