protection work on nh-10 in the state of sikkim on item rate basis ( retender ) protection work on nh-10 in the state of sikkim on item rate basis -2 excavation for structures ( earth work in excavation of foundation of structures as per drawing and technical specification, including setting out, construction of shoring and bracing, removal of stumps and other deleterious matter, dressing of sides and bottom, backfilling with approved material. ) i. ordinary soil ( a ) manual means ( depth upto 3m ) 3 plain / reinforced cement concrete in open foundation complete as per drawing and technical specifications pcc grade m15 4 providing and laying plump concrete in 1:2:4 c.c ( 1 cement 2 coarse sand, 4 clean hard graded stone chips of 20mm down nominal gauge ) with 50% clean hard stone of sizes not exceeding 15cm including shuttering, compacting and curing complete, as per the direction of engineer in charge 5 providing weep holes in brick masonry / plain / reinforced concrete abutment, wing wall / return wall with 100 mm dia pvc pipe, extending through the full width of the structure with slope of 1v :20h towards drawing foce. complete as per drawing and technical specifications 6 back filling behind abutment, wing wall and return wall complete as per drawing and technical specification ( a ) granular material 7 cement mortar 1:3 ( 1 cement :3 sand ) for 25 mm thick coping