ADVANTAGES AND DISADVANTAGES OF WATER BOUND MACADAM

  • Advantages - water Bound Macadam is superior in quality because the materials are carefully graded and the resulting mass is almost voidless compacted mass. The interlocking of aggregates particles imparts adequate strength of the materials selected for filling the voids . These ensure non entry of the plastic mstermat of the sub grade into the voids .


  • Disadvantages- the stone pieces used in water bound macadam road are keyed together by means of sand and clay and no other cementing material  is used . The bending effects of sand and clay depends upon the pressure of moisture. When the first moving vehicle passes over a W. B. M. Road, the slurry of sand and clay is sucked out by the pneumatic wheel types , the stone pieces get disturbed and finally road surface is disintegrated . Due to this factor , the w.B.M. roads are not suitable for fast moving vehicles with wheel types . These roads are only suitable for slow moving iron wheeled traffic such as tonges , bullocks carts etc, constant use of road by iron wheels , the road matal gets crushed . Considering these important factors , it may be inferred that a w.b.m. road survives only for a short time
A water bound macadam is less costlier as compared to bituminous base course

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