4: Earth Works, Excavation and embankment
4.1 Site clearance: The price Includes excavation in all types of SOILS (even rock Layers) up to depth" between 0.3 to 0.5m according to site. 4.2 Excavation of overburden Excavation In any kind of "soil starting at existing ground Levels, Including removal of surplus excavated materials from site to an approved dumping areas, complete specified In the drawings, all according to specification and site engineer instructions. 4.2.1 Open channel spillway Excavation.
4.2.2 Dam Body Excavation.
4.3 Excavation of hard rock Excavation in any kind of rock starting at rock line levels , including removal of surplus excavated materials from site to an approved dumping areas, complete specified In the drawings, all according to specification and site engineer instructions
4.3.1 Open channel spillway Excavation.
4.3.2 Dam Body Excavation.
4.4 Earth Works: Supply and compaction rockfill materials out of quarry area and Excavations of the dam to reach the saund rock layer and spillway area . the materials should be compacted according to specification and standards at optimum moisture content to layers not exceeding the lift height after compaction. The coat Includes all tasts and required works according to specification and site engineer's approval.
4.1 Zone A Well graded, selected, compacted rock used to provide bearing support for concrete face and emergency drain at left height not more than 40cm.
4.4.2 Zone B: Smaller sized rock from quarry, and rock of good quality from foundation Excavation and spillway excavation, computed to reduce concrete face settlement and able to carry the main water Load with maximum rock size in 600mm at lift height not more than 80 cm.
4.4.3 Zone c: largest and best quality of rockt available. Large slab by rock: should not be placed in this fill because they land to bridge causing large voids that may result in excessive settlement should the rock break with maximum rock size of this zone 900mm at lift height from 1 to 2 m according rock quality and size,
4.4.4 Cemented Grouted Rip-Rapt Cemented Grouted Rip-Rapt of sound reek of thickness about 250mm and mortar of grade C15 with total thickness of 0.3m.
Masonry Work at cut off Supply and compact rockfill .
4.4.5 materials mix with concrete at ratio 60% rock to 40% concrete C15, in rockfill section as shown an drawing.
4.4.6 base Corse Aggregates at dam Crest: Supply and install base Corse Aggregated at dam Crest. Materials shall be furnished, crusted and screened, mixed with water, placed, spread„ compacted and finished. All works shall be as specified In specification and undersite engineer's instructions.