What is BM and DBM?

Bituminous Macadam (BM)

This is a recipe type mix produced that gain no kind of quality in terms of strength and volumetric. The void content is 20 to 25% higher than the dense graded bitumen (DBM). The DBM have a void content of 3 to 5%. The BM have high potential to attract water and moisture.

What is the meaning of BM in road construction?

2.2 Bituminous macadam (BM) shall consist of mineral aggregate and appropriate binder, mixed in a hot mix plant and laid with a mechanized paver. It is an open graded mixture suitable for base course. It is laid in a single course or in a multiple layers on a previously prepared base.

What is DBM laying?

Dense Bituminous Macadam (DBM) Preparation and Laying Methodology. Description. The DBM materials shall be laid by a self-propelled sensor paver finisher equipped with a hopper, delivery augers and capable of spreading, tamping and finishing the mix to specified grade, lines and cross-section.

What is BM and BC in road construction?

1)Bituminous Macadam(BM) 50mm/75mm/100mm. 2)Bituminus Concrete (BC)

What is VG in bitumen?

Viscosity Grade Bitumen (Asphalt) is a Bitumen grade mostly used as a Paving Grade and it's suitable for road construction and for the asphalt pavements producing with premier attributes. VG Bitumen is usually used in the production of hot mix asphalt.

BITUMINOUS MACADEM_DENSE BITUMINOUS MACADEM | SEMI DENSE BITUMINOUS CONCRETE_BITUMINOUS CONCRETE

What is the difference between DBM and BC?

DBM (Dense Bituminous Macadam) & BC (Bituminous Concrete) are the top most layers of an Bituminous Top Roads, whose thickness is determined my MSA & CBR. CBR- California Bearing Ratio is a method of determining the mechanical strength & Load bearing capacity of soil.

What means macadam?

macadam • \muh-KAD-um\ • noun. : a roadway or pavement of small closely packed broken stone. Examples: The sloping, curved street saw light traffic and had a smooth macadam surface that made it popular with skateboarders. "

What is DBM in asphalt?

Dense Bituminous Macadam (DBM) is a binder course used for roads with more number of heavy commercial vehicles and a close-graded premix material having a voids content of 5-10 per cent.

What is GSB road?

Granular Sub-base (GSB) consists of laying and compacting well graded material on prepared sub-grade in accordance with the specifications.: GSB layer is intermediate layer in between Sub-grade and Wet mix macadam. GSB layer is laid in roads and higway works due to its properties .

What is the difference between BM and BC?

It is a dense mass as compared to BM and is provided as surfacing layer in bitumenous roads/ surfaces. Whereas, Bitumen mecadam is a mixture of stone aggregate only binded with bitmen and has porisity but more compressive strength that's why it is used as strengthening layer to increase the strength of the pavement.

How do you calculate bitumen content in BM?

What is semi dense bituminous macadam?

Semi Dense Bituminous Macadam is a binder that is laid after the BM course to obtain smoother finish on road surfaces. This is used in small roads of width less than 9 Meters. This course is laid directly on the wet mix macadam in smaller roads with a thickness of 25-30 mm.

What is WBM and WMM?

WBM(Water Bound Macadam) conventional method and WMM(Wet Mix Macadam) modern technology- are base course layers for Pavement/Road design. In case of WBM stone aggregates and binders are overlaid on one another at the time of construction.

What is difference between PQC and DLC?

PQC stands for Pavement Quality Concrete made with larger size aggregates following IRC specifications and laid over a Dry Lean Concrete(DLC), concrete subbase course. PQC construction is explicitly used for highway concrete pavements and runway pavements to take heavy loads.

How is GSB calculated?

Gsb = Bulk dry specific gravity of the total aggregate P1,P2,Pn = Percentages by weight of aggregates, 1,2,n; G1,G2,Gn = Bulk specific gravities of aggregates 1,2,n. The bulk specific gravity of mineral filler is difficult to determine accurately at the present time.

What is the difference between macadam and asphalt?

is that asphalt is a sticky, black and highly viscous liquid or semi-solid, composed almost entirely of bitumen, that is present in most crude petroleums and in some natural deposits while macadam is (uncountable) the surface of a road consisting of layers of crushed stone (usually tar-coated for modern traffic).

Why is macadam important?

McAdam's renown is due to his effective and economical construction, which was a great improvement over the methods used by his generation. He emphasized that roads could be constructed for any kind of traffic, and he helped to alleviate the resentment travelers felt toward increasing traffic on the roads.

What is bituminous concrete pavement?

Bituminous concrete is a type of construction material used for paving roads, driveways, and parking lots. It's made from a blend of stone and other forms of aggregate materials joined together by a binding agent. This binding agent is called "bitumen" and is a by-product of petroleum refining.

What is water macadam road?

WBM road means water bound macadam road. The wearing surface of WBM road consist of clean and crushed aggregates which are mechanically interlocked by rolling operation. The material is bound with filler material (which are also called as screenings) and water, laid on prepared base course.

What is mean by bituminous road?

What is Bituminous Road. Bituminous road consist of their surface with bituminous materials which is also called as Asphalt. It is sticky dark viscous liquid obtained from natural deposits like crude petroleum.

What is the meaning of 60 70 bitumen?

A grade of 60/70 bitumen means the penetration value is in the range 60 to 70 at standard test conditions which usually used as a Paving Grade. Bitumen 60/70 is applicable for the production of asphalt pavements with superior properties and for construction and maintenance of roads.

What is VG 40 grade bitumen?

VG-40 is used in highly stressed areas such as intersections, near toll booths and truck parking lots instead of 30/40 penetration grade. Because of higher viscosity, stiffer Bitumen mixes can be produced to amend resistance to shoving and other problems related to higher temperature and heavy traffic loads.

Why VG 30 bitumen is used?

VG-30 BITUMEN: VG-30 is primarily used to construct extra heavy duty Bitumen pavements that need to endure substantial traffic loads. It can be used in lieu of 60/70 Penetration grade.

What is the temperature of bitumen?

The bitumen temperature should be well within the limits specified. The viscosity of heated bitumen shall be between 150 to 300 conti stokes for which the normal temperature range for paving bitumen is between 150 to 177°C.