The maximum thickness of a single compacted layer base can be up to 250 mm upon approval of the Engineer. The thickness of single compacted Wet Mixed Macadam (WMM) Base shall not be less than 75 mm. It shall be laid on one or more layers as per line and level, grade and cross-section shown in the drawing or as directed by the Engineer. The material is well mixed with water and rolled to a dense mass. Wet Mix Macadam consists of laying spreading and compacting of clean, crushed, well-graded granular materials on a prepared and approved Granular sub-Base.
ROAD MIX BASE FREE
The material shall be free from organic or other deleterious constituents. The material to be used for the work shall be natural sand, crushed gravel, crushed stone, crushed slag, or a combination thereof depending upon the grading required use of material like brick metal, kankar and crushed concrete shall be permitted in the lower sub-base. SUB BASE (GSB) – it is being laid in road work because it plays two major rolesĢ- it provides a good sub-base to laid base layer on it.
It is a mixture of fractured rock, sand, and soils. Road base is used as a base layer under many projects. GSB material is a mix of sand & gravels, crushed stone & broken rock. 1 yard is equal to approximately 1.3 tons.GSB providing resistance against rutting.GSB reducing to stresses applied on subgrade layer.GSB act as a load bearing & strengthing component of pavement.1589, Variable Tire Pressure, Flowable Fill, Dust Control, and Base and Slope Stabilization.Agg are used below base coarse & above subgrade layer is known subbase layer, due to granular crushed agg its called granular subbase. This paper appears in Transportation Research Record No.Find a library where document is available.It was concluded that no clear benefit could be determined from using plant mix based on the sample of 10 projects, although the benefit of an adequate thickness of asphalt above the CTABC was clearly demonstrated. Backcalculated moduli for CTABC were higher for plant mix than for road mix, but the elastic moduli were similar for plant and road mix when determined by pulse-velocity testing. However, road mix sites had higher compressive strengths than did plant mix sites. Plant mix resulted in lower average deflections and lower deflections when sites were compared with equal thicknesses of asphalt above the base course. Neither the coefficient of variation nor a developed uniformity coefficient showed a significant difference between plant mix and road mix. Three possible benefits were considered: improved uniformity of material properties, reduced deflections, and increased strength or stiffness. Each had been tested with a falling-weight deflectometer and had been cored to determine layer thicknesses and properties either in the past or as part of the current effort. Ten projects known to have cement-treated base course were selected. COMPARISON OF ROAD MIX AND PLANT MIX CEMENT-TREATED AGGREGATE BASE COURSEĪ study was undertaken to determine the advantages of plant mix over road mix cement-treated aggregate base course (CTABC).
0 kommentar(er)
