Composition of Road Structure:Road Structure Cross Section is composed of the following components. Surface/Wearing Course. Base Course. Sub Base. Sub Grade1. Surface/Wearing Course in pavement cross section:The top layers of pavement which is in direct contact with the wheel of the vehicle. Usually constructed of material in which bitumen is used as binder materials.

• Cross Section Of A Roman Road Map

Bituminous Pavement:Consists of combination of mineral aggregate with bituminous binder ranging from inexpensive surface treatment ¼ in or less thick to. For good service throughout the full life bituminous pavement must retain following qualities. Freedom from cracking or raveling. Resistance to weather including the effect of surface water heat and cold. Resistance to internal moisture, particularly to water vapors. Tight impermeable surface or porous surface (if either is needed for contained stability of underlying base or subgrade).

A change of course would, for example, happen where the road was to cross a river and the Romans wanted to make the bridge at the narrowest point. Marking the actual course of the road. Once the course of the road was decided, the next task was for the course of the road between each marker to be established. Apr 12, 2010  Cross Section Of A Roman Road In Fuenterroble a cross-section of a Calzada Romana, or Roman road, has been opened to show how the roads were constructed by the Roman engineers. 'Roman Road Construction - Roman roads were constructed in layers. The average width of a road was 15 to 18 feet.

Smooth riding and non skidding surface.The design should be done so that to meet the above requirements for considerable number of years (need proper design and construction supervision). Pavement meeting all the requirements above have been product if six distinctly different construction processes as follows. Heat a viscous bituminous binder to make it fluid, then in a plant mix it with heated aggregate place and compact the mixture while it is hot. Use fluid bituminous binder, mix it with aggregate at normal temperature.

Mixing may be done at a plant (plant mix) or on the prepared roadway base (road mix). Spread and compact the mixture at normal temperature. Add solvent such as naphtha or kerosene to a viscous bituminous binder to make it fluid with aggregate at normal temperature by either plant or road mix methods. Spread and compact at normal temperature before solvent evaporates. Use fluid emulsion of viscose bituminous binder in water, mix it with aggregate at normal temperature by either plant or road mix method. Spread and compact at normal temperature before the emulsion breaks down with its components. Spread and compact clean crushed aggregate as for water bound macadam.

Over it spray heated dissolved or emulsified bituminous binder which penetrates open areas of the rock and binds the aggregate together. Thus is commonly called “Penetration Method”. Spread bituminous binder over the roadway surface then cover it with properly selected aggregate. This is commonly called the “Inverted Penetration Method”.Selections based on the requirements and economy, large volume of heavy vehicles, low traffic volume etc.

Base courseIt is the layer immediately under the wearing surface (Applies whether the wearing surface is bituminous or cement concrete and or more inch thick or is but a thin bituminous layer). As base course lies close under the pavement surface it is subjected to severe loading. The material in a base course must be of extremely high quality and its construction must be done carefully.

Granul ar Base Course. Macadam Base. In-water bound Macadam. Treated Bases3. Sub Base:It is layer of granular material provided above subgrade generally natural gravel. It is usually not provided on subgrade of good quality. It is also called granular subbase.

Function of Sub base in Road Cross Section. It enables traffic stresses to be reduced to acceptable levels in sub-grade in the Road Cross Section so that excessive deformation is prevented. It acts as a working plate form for the construction of upper pavement layers. Acts as a drainage layer, by protecting the sub grade from wetting up. It intercept upward movement of water by capillary action. It acts as a separating layer b/w subgrade and road base. By this it prevent the two layers from mixing up.b.

Characteristics of materials used in Sub Base:The subgrade material should be clean and free from organic matter and should be able to be compacted by roller, to form stable sub-base. The material should have following characteristic. Well graded uniformity coefficient (D60/D10) should not be less than 3. Fraction passing sieve #200 shall not be greater than 2/3rd of the fraction passing sieve #40.

Should have a L.L not greater than 25%. P.I not greater than 6. CBR should not be less than 25.

See also:. In coarse grain, aggregate retained by #10 sieve,%age of wear shall not be greater than 5%. The max dia of any particle shall not be greater than 2/3ed of the layer thickness of sub-base. Typical particle size distribution for the sub-base (granular) when will meet strength requirement are. B.S Sieve Size% By mass of total Aggr.

Passing test sieve5010037.580 - 1002060 - 100530 - 1001.15170 - 750.39 - 5000755 - 25. To avoid intrusion of silt and clay material in sub-base from subgradeD15 (sub base).

Most people have heard of, and the, but it is the lesser known Wansdyke in the West Country that is perhaps the most mysterious of them all!Stretching for 35 miles through the countryside of and, this large defensive earthwork was built some 20 to 120 years after the had left Britain. Set to a east-to-west alignment, it is thought that whoever built the dyke was defending themselves against invaders from the north. But who were these invaders?Although there is a fair amount of discussion around this subject, it is thought that it was built by the native Britons as a defensive measure against the who were expanding their territory from the east and the north.It is also thought that by 519 the West Saxons (who would later come to create the ) had their advance halted somewhere along the / Wiltshire border.

This theory is supported by the 9th century Historia Brittonum, and specifically its narrative of the Battle of Mons Badonicus. In this battle the native Britons, supposedly led by King Arthur himself, hit a decisive blow against the Anglo-Saxons and prevented them from gaining any more land for at least the next 50 years.Unfortunately there is no written account for where the Battle of Mons Badonicus actually took place, but one of the more popular theories was that it was around the area of Wansdyke. During the late 5th / early 6th century, this Somerset / Wiltshire area would have been the frontier of where native-Briton lands met Anglo-Saxon territory. It would have made sense then that the local Britons would have built some sort of defences knowing that invading hordes were coming their way!The Battle of Mons Badonicus.Although this is the most popular theory for why Wansdyke was constructed, it is not the only one. Another, albeit less popular hypothesis, is that the wall was built by the Romans themselves as a defensive measure against local Britons looking to take advantage of their crumbling authority in the late 4th century AD.

Some recent Roman coin finds around the Wansdyke area may give to weight to this argument, especially as the coins were struck during the final few years of. This argument is also backed up by the fact that Wansdyke is very similar in design to other late Roman earthworks such as Bokerley Dyke in.A photo of the Wansdyke on Tan Hill. Author: Trevor Rickard. Creative Commons Attribution Share-alike license 2.0The final theory behind Wansdyke was that it was built by the West Saxons to stop the pesky Britons from trying to retake their lands! The main argument behind this is that ‘Wansdyke’ literally means ‘Dyke of Woden’, Woden being the Anglo-Saxon god who used to carry the dead up to heaven. If indeed the Battle of Mons Badonicus took place near Wansdyke, then the huge losses that the Anglo-Saxons would have incurred may have led to them naming the Dyke after such a god.It is important to remember that Wansdyke was never actually a patrolled fortification. Instead, it was meant as both a fixed border between two territories as well as a buffer to slow down any invading forces.Wansdyke near BathToday the dyke has been broken in to three separate parts.

Cross Section Of A Roman Road Map

The eastern section (which runs through Wiltshire) is the best preserved, and even today the bank stands up to 14 feet high with the ditch at around 8 feet deep in places.The middle section of Wansdyke isn’t actually a dyke at all, but is formed by the remains of the to. The reason the road was integrated into the dyke was that it was actually raised above the ground and had the River Avon running behind it. This mean that the road was used as a bank, whilst the Avon was used as a makeshift ditch.A cross section of the Roman road at WansdykeThe final section of the dyke is the western section; here there are around 9 miles of visibile remains. Originally however this western section would have spanned all the way from Monkton Combe in Somerset across to the Avon river crossings in Bristol and Bath.In case you’re planning on visiting the area, we’ve marked some of the key parts of Wansdyke onto the map below.