This construction video briefly explains the technical specification for bitumen macadam and bitumen concrete essential for any road work.
Bitumen Macadam alias Asphalt Concrete is formed by blending aggregate, filler and bitumen and come in solid, medium or open graded on the basis of the end application.
Macadams are categorized into three primary layer categories like Base, Binder and Surface Course. It is applied as a binder course for roads where lots of heavy commercial vehicles pass through as well as a closed-graded premix materials exist with voids content 5-10 per cent. It has strong and long-lasting surface.
Bituminous concrete refers to a sort of construction material that is employed for paving roads, driveways, and parking lots. It is formed by mixing stone and other forms of aggregate materials combined jointly through a binding agent. This binding agent is known as “bitumen” and is a by-product of petroleum refining. It contains a dense, sticky texture like tar once heated, then develops a thick solid surface as soon as it gets dried. Bituminous concrete is also extensively recognized as asphalt in various parts of the globe.
This material does not include cement. It has typical black appearance. It is frequently placed right over a gravel base layer to build up new roads and parking lots, but may also be poured over prevailing concrete to patch-up or smooth out bumps and voids.
As soon as the bituminous concrete are poured onto the roadway, the surface is leveled and compacted through a large paving machines.
For Bituminous Macadam :-
1) Grade of bitumen should be vary from 60 to 70
2) Temperature at different stages :-
a) At the time of blending materials maximum temperature should be 1650C
b) At the time of laying, the temperature should be 1250C
c) At the time of rolling, the temperature should be 900C
3) Levels (tolerance) – At the time of rolling, the layers should be +6 M to -6 M.
4) Field Density Test – Here, compaction should be 98%; 1 test per 250 m2 of area.
To get the complete details, watch the following video.