Road Construction Process

Clearing and GrubbingNatural Ground CompactionEarth WorkStructure WorkSub gradeSub baseBase CourseAsphalt Wearing Course
Shoulder & Side Slopes

Clearing and Grubbing

The stage of development during which vegetation is cleared from land (clearing) and a root rake or similar device used to get rid of roots remaining within the soil (grubbing)
Within the bounds as directed and staked out by the Engineer, all brush and trees, except those selected by the Engineer to be saved, shall be cut level with the bottom, and every one surface junk, excluding vendible timber however together with fallen timber, slash limbs, brush, grass and weeds, shall be disposed of as hereafter set forth.
Within areas wherever excavation is going to be created and wherever the hill grade is a smaller amount than one meter higher than the initial ground level, all stumps and roots shall be grubbed out. Trees shall be felled towards the middle of the world to be cleared. Any brush or trees falling outside of the world to be cleared shall be captive back to the right-of-way and disposed of. The Contractor shall take all precautions against injury to alternative trees, traffic, structures, pole lines or property in his felling of trees, and he shall be answerable for any damages occurring within the performance of this work.
Timber from that forest merchandise are often factory-made shall be cleared of limbs and showing neatness heaped-up on the right-of-way as directed or permissible by the Engineer. Usable timber shall be the property of the Contractor and shall be far from the right-of-way before any payment by progressive estimate for work drained that space are going to be created.

Natural Ground Compaction

After CG next method is NGC, here natural ground in being compacted at needed quality
Soil compaction means the density of the soil will increase once it's compressed. In alternative words, the soil becomes denser and each liter of soil weighs a lot of once the pores area unit compressed. it's typically simple to know and gauge the results of soil compaction from observation a tractor over loose soil in wet conditions.

Back Fill (Embankment)

Earthwork is one in all the most important works concerned in construction. It involves the removal of dirt, in conjunction with any vegetation, before scraping and grading the world to the finished 'formation level'. ... it's essential that the strength of the subgrade is tested before wall starting
The hill consists of a series of compacted layers or lifts of appropriate material placed on high of every alternative till the extent of the subgrade surface is reached. The subgrade surface is that the high of the hill and also the surface upon that the molding is placed.
Before embankments area unit placed on natural soil slopes, they have to be ready. These strategies are required if the present fill slopes are chiseler than 4:1. to arrange the slope, benches of a minimum of ten feet broad area unit take away the slopes before the hill fill is placed. Compaction management is incredibly necessary component of hill construction

Structure Work

Structures like bridges, drifts and box culverts sometimes account for a high proportion of the entire value of a road. they're the weak links in an exceedingly road system, as a result of the damaging effects of floods or high precipitation area unit focused at the points wherever the water crosses the road. Their failure won't solely cause high replacement prices however may build the road useless for long periods.
For these reasons extreme care ought to be taken that appropriate structures area unit made within the best place attainable which the proper sort and style of the structures is chosen.
The location of the structures ought to be thought-about at the time of the primary survey once the preliminary alignment is chosen.

Sub grade

Heavy trucks and buses area unit frequently loading our pavements. These masses area unit transmitted through the pavement to the sub grade. In effect, the hundreds applied to the surface of the pavement area unit transmitted through the structure, deforming or otherwise destroying the integrity of the sub grade. however, the sub grade goes to react underneath the appliance of masses is of nice concern. As illustrated in Figure three.2, however the load gets transferred to the sub grade and the way the sub grade will handle that load includes a sturdy on the quality of the pavement. If the pavement is skinny as shown within the sketch, the strain obligatory by the load through the pavement is distributed over a tiny low space, creating for top stresses on the sub grade. If the sub grade is poorly ready (improper compaction, excessive wet, etc.) or includes a terribly low strength (such like extremely plastic clays), the sub grade cannot resist these high stresses

Sub base

In main road engineering, molding is that the layer of combination material arranged on the sub grade, on that the bottom course layer is found. it should be omitted once there'll be solely pedestrian traffic on the pavement, however it's necessary for surfaces utilized by vehicles.
Sub base is usually the most supporting layer of the pavement. Its role is to unfold the load equally over the sub grade. The materials used is also either unbound granular, or cement-bound. the standard of molding is extremely necessary for the helpful lifetime of the road and might survive the lifetime of the surface, which may be scrapped off and when checking that the molding remains in fitness, a brand new layer will be applied 
Unbound granular materials area unit sometimes crushed stone, crushed Scotia or concrete, or slate.

Base Course

Prior to placement of the bottom course, the underlying surface shall be ready by dressing, shaping, wetting or drying, and compacting of the underlying material to a minimum density of ninety-five as determined. Surfaces shall be cleansed of all foreign substances and scrap. Base course material shall be deposited and unfold during a uniform layer to the desired grades, and to such loose depth that once compacted to the density needed, the thickness is as indicated on the Drawings. parts of the layer that become segregated shall be removed and replaced with a satisfactory mixture, or shall be remixed to the desired gradation.

Wearing Course

The sporting course is that the higher layer in road, airfield, and waterfront construction. ... In versatile pavements, the higher layer consists of asphalt concrete, that's a construction combination with a hydrocarbon binder

Shoulder and Side Slopes

Shoulders area unit usually used on high, or intermediate speed restricted and non-limited access facilities, some rural contexts, additionally as intermediate-speed locations that don't have street sides. Shoulders give area to flee potential collisions or scale back their severity. They conjointly give a way of openness, causative to driver ease at higher speeds. Shoulders conjointly convey drain far away from the traveled manner