How is WBM road constructed?
The full form of WBM is Water Bound Macadam. It is the layer of road constructed from broken stone aggregates bound together by stone dust or screening material and water applied during construction and compacted by a heavy smoothed wheel roller.
How do you build road construction?
Steps in Bituminous Road Construction….
- Preparation of the existing base course layer. The existing surface is prepared by removing the pot holes or rust if any.
- Application of Tuck Coat.
- Preparation and placing of Premix.
- Rolling.
- Quality control of bituminous concrete construction.
- Finished surface.
Which material is required for construction of WBM roads?
The coarse aggregates used in W.B.M generally consists of hard varieties of crushed aggregates or broken stones. However, soft aggregates like over burnt bricks metal, kankar and laterite may be used.
What is the full form of WBM in road construction?
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 the difference between WMM and WBM?
In case of WBM stone aggregates and binders are overlaid on one another at the time of construction. But in case of WMM,aggregates and binding materials are premixed in a batching plant or in a concrete mixing machine and then brought to the site for overlaying and rolling.
Which is the defect in WBM road?
Poor Mix proportioning or inadequate thickness are main reasons for the lack of stability or strength of sub-base or base course. 2. Loss of Binding Action: Due to internal movements of aggregate in sub-base a base course layers under the stress applications, the component structures of the layer get disturbed.
What are the layers of road construction?
The road pavement structure layers are as follows.
- Subgrade or road bed.
- Sub base course.
- Base Course.
- Surface coarse or wearing course.
What is difference between WMM and WBM?
What is the density of WBM?
Effect on Maximum Dry Density (MDD): it is observed that WBM-A exhibited MDD of 20.60kN/m3 and WBM-B exhibited MDD of 22.66kN/m3, indicating 10% increase in MDD for WBM –B after partial replacement by steel slag, specific gravity of steel slag is higher compared to conventional aggregates.
Who invented WBM road?
WBM Stands for Water Bound Macadam which is the most commonly used road construction procedure for over more than 201 years. Pioneered by Scottish Engineer John Loudon McAdam around 1820 Macadam is a type of Road Construction.
What is a WBM road?
The broken stones of the base and surface course if any are bound by the stone dust in the presence of moisture is called WBM road. WBM stands for water bounded macadam which is the most commonly used road construction procedure for over more than 190 years. Scottish engineer John Loudon Macadam around 1820 macadam is a type of road construction.
How to prepare new layer of WBM roads?
The foundation for receiving the new layer of WBM roads may be either the sub grade or sub base or base course. This layer is thus prepare by scarifying and filling the depressions and patching the pot holes, the receiving surface is brought to the required grade and camber.
What is the construction cost of WBM road?
The construction cost of WBM road is comparatively low. WBM road no skilled labor is required. They are constructed from locally available material. WBM roads are maintained properly and from time to time.
How to construct a water bound macadam road?
Construction of water bound macadam road involves the following 6 basic steps as given below. Sub-grade act as a cushion for other layers i.e. In order to achieve durable road sub-grade should be strong.
https://www.youtube.com/watch?v=fw98pJjrLVo