Construction of flexible pavement

Basic method of Construction of flexible Pavement .

1. Construction of flexible Pavement .

2. INDEX Company Profile Introduction Types of pavement Component of flexible pavement Construction of Subgrade. Construction of subbase course. Construction of base course and bitumen layer.

3. Company Profile The Public Works Department establish in the year 1854. At that time PWD was responsible for the construction of roads,buildings,railways as well as flood control,irrigation and military works.The organization’s construction works is directly connected to the national programme of development and reconstruction. P.W.D

4. INTRODUCTION PAVEMENT- Pavement is load bearing and load distributery component of a road. PURPOSE OF PAVEMENT- Load support. Smoothness. Drainage. All weather operation. Direction and guidance.

5. TYPES OF PAVEMENT STRUCTURE – Flexible Pavement. (Hot mix asphalt (HMA) pavements) 2 . Rigid Pavement . (Portland cement concrete (PCC) pavements)

6. Components of flexible pavement. Soil Subgrade . Sub Base Course. Base Course. Surface Course.

7. Construction of Subgrade Materials - Selected Soil , Moorum , Gravel , Aggregate maximum 50 mm. Construction Method – The subgrade is constructed by spreading the loose soil and compacting the same at optimum moisture content of the soil in layer. The maximum compacted thickness of each layer is generally limited to 200 mm as per MORTH.

8. Construction of Sub base Course (GSB) Material used- Crushed stone Aggregates, Gravel, Coarse sand , Selected soil with less fine and low plasticity. CONSTRUCTION METHOD – GSB layer is constructed on the top of the prepared subgrade . The sub-base material is spread to uniform thickness and spesific cross slope . Then the moisture content of the material is checked and additional quantity of water required to bring up to the optimum moisture content is sprinkled at a uniform rate. The loose GSB layer is compected by roller.

9. Your Text Here Construction of base Course (wet mix macadam) Material used- Hard crushed aggregates and adequate proportion of water mixed thoroughly in a mixing plant. Construction Steps – WMM mix is prepared in a mixing plant. The WMM mix is transported to the site and spread using self propelled type paver finisher machine. WMM layer is compacted using a vibratory roller of minimum static weight of 10 tonnes.and compacted thickness in less than 200mm. After the WMM layer is dried for at least 24 hours in dry weather.

10. WET MIX MACADAM PLANT

11. Transported Apply on ground

12. Construction of Bituminous Pavement layers Three types of bituminous layers- Bituminous Macadam. Penetration Macadam. Bult up spray Grout.

13. Bituminous Macadam It consist of crushed aggregate and bituminous binder heated and mixed in a hot mix plant at specified temperature , transported to the construction site, laid with a mechanical pawer and compacted by roller. Material used : Bitumen binder of grade VG -30,20 and Max size of aggregate 50mm.

14. Bituminous Penetration Macadam Base Course The coarse aggregate of specified size are first spread and compacted well in dry state. Compected thickness 50-75 mm. After compacting of dry aggregates, hot bituminous binder of specified grade is spread in large quantity on the top of this layer. Filling up a part of void and binding by key aggregate.

15. Bult up spray grout base course It consist of a two layer composite construction of compacted crushed stone aggregate with bituminous binder applied after each layer and key aggregate placed on the top surface of the second layer.

16. Thank You Submitted By Mr. Deepak Bhatt Submitted to : Mr. Jaibeer Chand U.I.T Dehradun