Construction Upgradation Of Nagsari A AND B Narikote And Ladda Road, including Moori Kothiyan Road, Kalaroos Kupwara (Phase I under CRF)

Centering & shuttering incl. strutting, propping etc. and removal of form work for Foundations, footings, bases of columns etc.

Earth work in bulk excavation by mechanical means (hydraulic excavator) over areas (exceeding 30 cm in depth, 1.5 m in width as well as 10 m2 on plan) including disposal of excavated earth lead upto 50 meters and lift upto 1.5 m, as directed by Engineer-in-Charge.: Ordinary rock

Filling available excavated earth (excluding rock) in trenches, plinth, sides of foundations etc. in layers not exceeding 20 cm in depth, consolidating each deposited layer by ramming and watering, lead upto 50 m and lift upto 1.5 m. Serviceable material available

Earth work in bulk excavation by mechanical means (hydraulic excavator) over areas (exceeding 30 cm in depth, 1.5 m in width as well as 10 m2 on plan) including disposal of excavated earth lead upto 50 meters and lift upto 1.5 m, as directed by Engineer-in-Charge. All kinds of soil

Earth work in bulk excavation by mechanical means (hydraulic excavator) over areas (exceeding 30 cm in depth, 1.5 m in width as well as 10 m2 on plan) including disposal of excavated earth lead upto 50 meters and lift upto 1.5 m, as directed by Engineer-in-Charge. Ordinary rock

Filling available excavated earth (excluding rock) in trenches, plinth, sides of foundations etc. in layers not exceeding 20 cm in depth, consolidating each deposited layer by ramming and watering, lead upto 50 m and lift upto 1.5 m. Serviceable material available

Earth work in bulk excavation by mechanical means (hydraulic excavator) over areas (exceeding 30 cm in depth, 1.5 m in width as well as 10 m2 on plan) including disposal of excavated earth lead upto 50 meters and lift upto 1.5 m, as directed by Engineer-in-Charge. All kinds of soil

Earth work in bulk excavation by mechanical means (hydraulic excavator) over areas (exceeding 30 cm in depth, 1.5 m in width as well as 10 m2 on plan) including disposal of excavated earth lead upto 50 meters and lift upto 1.5 m, as directed by Engineer-in-Charge. Ordinary rock

Filling Good earth bought from borrow pits (excluding rock) in trenches, plinth, sides offoundations etc. in layers not exceeding 20 cm in depth, consolidating each deposited layer by ramming and watering, lead upto 50 m and lift upto 1.5 m. including all complete Serviceable material available

Part B Road: Construction of granular sub-base by providing close graded Material conforming to specifications, mixing in a mechanical mix plant at OMC, carriage of mixed material by tippers to work site, for all leads & lifts, spreading in uniform layers of specified thickness with motor grader on prepared surface and compacting with vibratory power roller to achieve the desired density, complete as per specifications and directions of Engineer-in-Charge. With material conforming to Grade-I (size range 75 mm to 0.075 mm) having CBR Value-30

Supplying and stacking at site Graded crushed stone aggregate of size 63 mm to 45 mm

Supplying and stacking at site stone screening of size 13.2 mm nominal size (Type A)

Supplying and stacking at site Moorum

Carriage of material by M.T incl. loading/unloading & stacking complete. Sand av lead 50 km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Below 40 mm av lead 20km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Above 40 mm av lead 20 km

Drain: Earth work in excavation by manual means in trenches for foundations, drains, pipes, cables etc. (Not exceeding 1.5 mtr in width & for shafts, wells, cesspits & the like not exceeding 10 sqm on plan, depth upto 1.5 m including disposal of excavated earth upto 1 mtr from cutting edge, disposed earth is to be levelled & neatly dressed. All kinds of soil

Providing & laying in position cement concrete of specified grade excluding the cost of centering and shuttering -- All work upto plinth level 1:5:10 (1 cement : 5 fine sand : 10 graded stone aggregate 40 mm nominal size)

Providing & laying in position cement concrete of specified grade excluding the cost of centering and shuttering -- All work upto plinth level 1:3:6 (1 cement : 3 coarse sand : 6 graded stone agg. 20 mm nominal size) crushed. Incl. 20% Plum

Cement concrete flooring 1:2:4 (1 cement : 2 coarse sand : 4 graded stone agg.) finished with a floating coat of neat cement including cement slurry, but excl. the cost of nosing of steps etc. 50 mm thick with 20 mm nominal size stone aggregate.

12 mm cement plaster of mix 1:6 (1 cement: 6 fine sand).

Centering & shuttering incl. strutting, propping etc. and removal of form work for Foundations, footings, bases of columns etc.

Carriage of material by M.T incl. loading/unloading & stacking complete. Sand av lead 50 km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Below 40 mm av lead 20km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Above 40 mm av lead 20 km

B Wall: Earth work in excavation by manual means in trenches for foundations, drains, pipes, cables etc. (Not exceeding 1.5 mtr in width & for shafts, wells, cesspits & the like not exceeding 10 sqm on plan, depth upto 1.5 m including disposal of excavated earth upto 1 mtr from cutting edge, disposed earth is to

Providing & laying in position cement concrete of specified grade excluding the cost of centering and shuttering -- All work upto plinth level 1:5:10 (1 cement : 5 fine sand : 10 graded stone aggregate 40 mm nominal size)

Providing & laying in position cement concrete of specified grade excluding the cost of centering and shuttering -- All work upto plinth level 1:3:6 (1 cement : 3 coarse sand : 6 graded stone agg. 20 mm nominal size) crushed. Incl. 20% Plum

Random Rubble masonry with hard stone in foundation and plinth including leveling up with cement concrete 1:6:12 (1 Cement : 6 coarse sand : 12 graded stone aggregate 20mm nominal size) upto plinth level and curing complete with: Cement mortar 1:6 (1 Cement : 6 coarse sand)

Cement concrete flooring 1:2:4 (1 cement : 2 coarse sand : 4 graded stone agg.) finished with a floating coat of neat cement including cement slurry, but excl. the cost of nosing of steps etc. 50 mm thick with 20 mm nominal size stone aggregate.

Dry Random Rubble masonry with hard stone in foundation & plinth without bond stone

12 mm cement plaster of mix 1:6 (1 cement: 6 fine sand).

Providing and laying damp-proof Course 50 mm thick with cement concrete 1:2:4 (1 cement:2 coarse sand: 4 graded stone aggregate 20 mm nominal size) and curing complete

Centering & shuttering incl. strutting, propping etc. and removal of form work for Foundations, footings, bases of columns etc.

Carriage of material by M.T incl. loading/unloading & stacking complete. Sand av lead 50 km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Below 40 mm av lead 20km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Above 40 mm av lead 20 km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone av lead 9 km

R Wall: Earth work in excavation by manual means in trenches for foundations, drains, pipes, cables etc. (Not exceeding 1.5 mtr in width & for shafts, wells, cesspits & the like not exceeding 10 sqm on plan, depth upto 1.5 m including disposal of excavated earth upto 1 mtr from cutting edge, disposed earth is to be levelled & neatly dressed. All kinds of soil

Providing & laying in position cement concrete of specified grade excluding the cost of centering and shuttering -- All work upto plinth level 1:5:10 (1 cement : 5 fine sand : 10 graded stone aggregate 40 mm nominal size)

Providing & laying in position cement concrete of specified grade excluding the cost of centering and shuttering -- All work upto plinth level 1:3:6 (1 cement : 3 coarse sand : 6 graded stone agg. 20 mm nominal size) crushed. Incl. 20% Plum

Random Rubble masonry with hard stone in foundation and plinth including leveling up with cement concrete 1:6:12 (1 Cement : 6 coarse sand : 12 graded stone aggregate 20mm nominal size) upto plinth level and curing complete with: Cement mortar 1:6 (1 Cement : 6 coarse sand)

Dry Random Rubble masonry with hard stone in foundation & plinth without bond stone

Providing and laying damp-proof Course 50 mm thick with cement concrete 1:2:4 (1 cement:2 coarse sand: 4 graded stone aggregate 20 mm nominal size) and curing complete

Centering & shuttering incl. strutting, propping etc. and removal of form work for Foundations, footings, bases of columns etc.

Carriage of material by M.T incl. loading/unloading & stacking complete. Sand av lead 50 km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Below 40 mm av lead 20km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Above 40 mm av lead 20 km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone av lead 9 km

Earth Work: Earth work in bulk excavation by mechanical means (hydraulic excavator) over areas (exceeding 30 cm in depth, 1.5 m in width as well as 10 m2 on plan) including disposal of excavated earth lead upto 50 meters and lift upto 1.5 m, as directed by Engineer-in-Charge.: ( All kinds of soil)

Providing & laying in position cement concrete of specified grade excluding the cost of centering and shuttering -- All work upto plinth level 1:5:10 (1 cement : 5 fine sand : 10 graded stone aggregate 40 mm nominal size)

Providing and laying cement concrete in retaining walls, return walls, walls (any thickness) including attached pilasters, columns, piers, abutments, pillars, posts, struts, butteresses, string or laces, courses, parapets,coping, bed blocks, anchor blocks, plain window sills,sunken floors fillets etc. upto floor five level, excluding the cost of centring, shuttering and finishing-1:3:6 (1 cement:3 coarse sand:6 graded stone aggregate 20mm nommal size (Crushed) incl 20 % plum

Centering & shuttering incl. strutting, propping etc. and removal of form work for Retaining walls, return walls, walls (any thickness) including attached plasters, buttresses, plinth and string courses etc.

Cement concrete flooring 1:2:4 (1 cement : 2 coarse sand : 4 graded stone agg.) finished with a floating coat of neat cement including cement slurry, but excl. the cost of nosing of steps etc. 50 mm thick with 20 mm nominal size stone aggregate.

Hand-packing stones in wire-crates; including cost of crates and stones

Stone filling hand packed including supply of stones front of D/wall

Providing and laying non-pressure of specified class R.C.C. pipes including collars/spigot jointed with stiff mixture of cement mortar in the proportion of 1:2 (1 cement: 2 fine sand) including testing of joints etc. complete Non pressure NP-3 class (Medium duty) R.C.C. pipes 1000 mm dia. R.C.C. pipe (laying by manual/mechanical means)

Filling available excavated earth (excluding rock) in trenches, plinth, sides of foundations etc. in layers not exceeding 20 cm in depth, consolidating each deposited layer by ramming and watering, lead upto 50 m and lift upto 1.5 m

Carriage of material by M.T incl. loading/unloading & stacking complete. Sand av lead 50 km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Below 40 mm av lead 20km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Above 40 mm av lead 20 km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone av lead 9 km

Culvert: Demolishing R.C.C. work manually/by mechanical means including stacking of steel bars and disposal of unserviceable material within 50 meters lead as per direction of Engineer-in-charge.

Earth work in excavation by mechanical means (hydraulic excavator) in trenches for foundations, drains, pipes, cables etc. (not exceeding 1.5min width)and for shafts,wells,cess pits and the like not exceeding10sqm on plan, including dressing of sides and ramming of bottoms lift upto1.5m, including

Providingandlayingof stonesoling/boulders (Hand Packed)including ramming, dressing and watering all complete.(Incl. all sorts of carriage)

Providingand laying in position cement concrete of specified grade excluding the cost of centering and shuttering. All work up to plinth level. 1:4:8 (1 cement: 4 coarse sand: 8 graded stone aggregate 40mm nominal) crushed.

Providing and laying in position specified grade of reinforced cement concrete including curing but excluding the cost of centering, shuttering, finishing and reinforcement. All works upto plinth level in 1:1½:3 (1 cement :1½ coarse sand: 3 graded stone aggregate 20 mm nominal size)

Reinforced cement concrete work in beams suspended floors , roofs having slope upto 15 degree, landings balconies, shelves, chajjas, lintels, bands, plain window sills, staircase and spiral stair cases upto floor five level excluding the cost of centering shuttering, finishing and rienforcement with in 1:1.5:3 (1 cement : 1.5 coarse sand: 3 graded crushed stone aggregate 20 mm nominal size)

Providing and laying in position cement concrete of specified grade including curing but excluding the cost of centring and shuttering. All work upto plinth level with: 1:3:6 (1 cement : 3 coarse sand : 6 graded stone aggregate 20 mm nominal size)

Filling in room using Second class sand/ boulder back fillling in rooms hand packed including ramming watering all complete.

Steel reinforcement for R.C.C. work including straightening, cutting, bending, placing in position and binding all complete above plinth level ThermoMechanically Treated bars of grade Fe-500D or more. @ 135 kg/cum

Centering & shuttering incl. strutting, propping etc. and removal of form work for Foundations, footings, bases of columns etc.

Centering & shuttering incl. strutting, propping etc. and removal of form work for Suspended floors, roofs, landings, balconies andaccess platforms.

Centering & shuttering incl. strutting, propping etc. and removal of form work for Edges of slabs and breaks in floors and walls under 20 cm wide

Centering & shuttering incl. strutting, propping etc. and removal of form work for Lintel, beams, plinth beams, girders, bressumers and cantilevers.

Centering & shuttering incl. strutting, propping etc. and removal of form work for Walls (any thickness) including attached pilasters,

Carriage of material by M.T incl. loading/unloading & stacking complete. Sand av lead 50 km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Below 40 mm av lead 20km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Above 40 mm av lead 20 km

Bridge: Earth work in bulk excavation by mechanical means (hydraulic excavator) over areas (exceeding 30 cm in depth, 1.5 m in width as well as 10 m2 on plan) including disposal of excavated earth lead upto 50 meters and lift upto 1.5 m, as directed by Engineer-in-Charge.

Extra rates for quantities of work executed:In or under water and/ or liquid mud, including pumping out water as required

Extra for every additional lift of 1.5 m or part thereof in excavation/banking excavated or stacked material :

Providing and laying of stone soling (Hand Packed) including ramming, dressing and watering and carriage up to site.

Pumping out water caused by springs, tidal or river seepage, broken water mains or drains and the like

Providing and laying in position cement concrete of specified grade excluding the cost of centering and shuttering. All work up to plinth level. 1:3:6 (1 cement: 3 coarse sand: 6 graded stone aggregate 40mm nominal) crushed

Providing and laying in position machine batched and machine mixed design mix M-25 grade cement concrete for reinforced cement concrete work, using cement content as per approved design mix, including pumping of concrete to site of laying but excluding the cost of centering, shuttering, finishing and reinforcement, including admixtures in recommended proportions as per IS: 9103 to accelerate, retard setting of concrete, improve workability withoutimpairing strength and durability as per direction of Engineer-incharge.Note: - Cement in this item is @ 330 kg/ cum. Excess or less cement used as per design mix is content considered payable or recoverable separately. All works upto plinth level

Providing and laying in position machine batched and machine mixed design mix M-30 grade cement concrete for reinforced cement concrete work, using cement content as per approved design mix, including pumping of concrete to site of laying but excluding the cost of centering, shuttering, finishing and reinforcement, including admixtures in recommended proportions as per IS: 9103 to accelerate, retard setting of concrete, improve workability without impairing strength and durability as per direction of Engineer-incharge.All works above plinth level upto floor V level Extra for providing richer mixes at all floor levels. Note:- Excess/ less cement over the specified cement content used is payable/ recoverable separately. Providing M-30 grade concrete instead of M-25 grade BMC/RMC. (Note:- Cement content considered in M-30 is @ 340 kg/cum)

Providing and laying in position machine batched and machine mixed design mix M-40 grade cement concrete for reinforced cement concrete work, using cement content as per approved design mix, including pumping of concrete to site of laying but excluding the cost of centering, shuttering, finishing and reinforcement, including admixtures in recommended proportions as per IS: 9103 to accelerate, retard setting of concrete, improve workability without impairing strength and durability as per direction of Engineer-incharge. All works above plinth level upto floor V level Extra for providing richer mixes at all floor levels. Note:- Excess/ less cement over the specified cement content used is payable/ recoverable separately. Providing M-40 grade concrete instead of M-25 grade BMC/RMC. (Note : Cement content considered in M-40 is @ 360 kg/cum)

Reinforcement of R.C.C work including straightening, cutting, bending, placing in position and binding all complete with Thermo-Mechanically Treated bars.

Providing and laying of boulders of nominal size 150mm 300mm behind wall (Hand Packed) including carriage up to site

Centering & shuttering incl. strutting, propping etc. and removal of form work for Foundations, footings, bases of columns etc.

Centering & shuttering incl. strutting, propping etc. and removal of form work for Suspended floors, roofs, landings, balconies andaccess platforms.

Centering & shuttering incl. strutting, propping etc. and removal of form work for Columns, pillars, piers, abutments, posts and struts.

Providing weep holes in Reinforced concrete abutment, wing wall/ return wall with 100 mm dia AC pipe, extending through the full width of the structure with slope of 1V :20H towards drawing face. Complete as per drawing and Technical Specifications.

Structural steel work in built up sections, trusses and framed work, including cutting, hoisting, fixing in position and applying a priming coat of approved steel primer all complete. Welded sections.

Providing and fixing of Elastromric bearing lateral / vertical as per designer specification to take design load including all fixtures

Providing & laying bitumen mastic wearing course (as per specifications) with industrial bitumen of grade 85/25 conforming to IS : 702, prepared by using mastic cooker & laid to required level and slope, including providing antiskid surface with bitumen pre-coated fine grained hard stone chipping of approved size at the rate of 0.005 cum per 10 sqm& at approximate spacing of 10 cm centre to centre in both directions, pressed into surface protruding 1 mm to 4 mm over mastic surface, includ

Providing and fixing 100 mm diameter and 60 cm long rain water spout in cement mortar 1:4 ( 1 cement : 4 fine sand) Stone ware spout. 100 mm dia.

1.0 Mtr dia HPC: Earth work in excavation by mechanical means (hydraulic excavator) in trenches for foundations, drains, pipes, cables etc. (not exceeding 1.5 m in width) and for shafts, wells, cesspits and the like not exceeding 10 sqm on plan, including dressing of sides and ramming of bottoms lift upto 1.5 m, including getting out excavated earth and disposal of surplus excavated earth as directed, within a lead of 50 metres All kinds of soil @ 60% ordinary rock @ 20% & hard rock @ 20%

Carriage of material by M.T incl loading/unloading & stacking complete Sand average lead 50km

Carriage of material by M.T incl loading/unloading & stacking complete Stone aggregates average lead 20km

Painting steel work with deluxe multi surface paint of required shade to give an even shade. Two or more coats applied @ 0.90litre/10sqm over an under coat of primer applied @ 0.80litre/10sqm of approved brand and manufacture

Crate Wall: Earth work in excavation by mechanical means (hydraulic excavator) in trenches for foundations, drains, pipes, cables etc. (not exceeding 1.5 m in width) and for shafts, wells, cesspits and the like not exceeding 10 sqm on plan, including dressing of sides and ramming of bottoms lift upto 1.5 m, includinggetting out excavated earth and disposal of surplus excavated earth as directed, within a lead of 50 metres All kinds of soil

Hand-packing stones in wire-crates; including cost of crates and stones Size 6m x 1.2 x 1.2

Carriage of material by M.T incl loading/unloading & stacking complete Stone av lead 9 km

Approach Road: Filling good earth bought from borrow pits (excluding rock) in trenches, plinth, sides of foundations etc. in layers not exceeding 20 cm in depth, consolidating each deposited layer by ramming and watering, lead upto 50 m and lift upto 1.5 m. inluding all complete

Construction of granular sub-base by providing close graded Material conforming to specifications, mixing in a mechanical mix plant at OMC, carriage of mixed material by tippers to work site, for all leads & lifts, spreading in uniform layers of specified thickness with motor grader on prepared surface and compacting with vibratory power roller to achieve the desired density, complete as per specifications and directions of Engineer-in-Charge. With material conforming to Grade-I (size range 75 mm to 0.075 mm) having CBR Value-30

Providing, laying, spreading and compacting graded stone aggregate (size range 53 mm to 0.075 mm ) to wet mix macadam (WMM) specification including premixing the material with water at OMC in mechanical mix plant, carriage of mixed material by tipper to site, for all leads & lifts, laying in uniform layers with mechanical paver finisher in sub- base / base course on well prepared surface and compacting with vibratory roller of 8 to 10 tonne capacity to achieve the desired density, complete as per specifications and directions of Engineer-in-Charge

Supplying and stacking at site Graded crushed stone aggregate of size 63 mm to 45 mm including stone screening of size 13.2 mm nominal size (Type A),Moorum all complete

Providing and applying tack coat using hot straight run bitumen of grade VG-10, including heating the bitumen, spraying the bitumen with mechanically operated spray unit fitted on bitumen boiler, cleaning and preparing the existing road surface as per specifications on WBM @0.75 kg/ sqm

Providing & laying bituminous macadam using crushed stone aggregates of specified grading premixed with bituminous binder, transported to stie by tippers, laid over a previously prepared surface with paver finisher to the required grade, level and alignment and rolling with smooth wheeled, vibratory and tendem rollers as per specifications to achieve the desired compaction and density, complete as per specifications and directions of Engineer- in- charge 50 mm average compacted thickness with bitumen of grade VG-30 @3.5% (percentage by weight of total mix) prepared in Drum Type hot Mix Plant of 60-90 TPH capacity

Providing and laying semi- dense Bituminous concrete using crushed stone aggregates of specified grading, premixed with bituminous binder and filler, transporting the hot mix to work site by tippers, laying with paver finisher equipped with electronic sensor to the required grade, level and alignment and rolling with smooth wheeled, vibratory and tandem rollers to achieve the desired compaction and density as per specification, complete and as per directions of Engineer-in-Charge. 25 mm compacted thickness with bitumen of grade VG30 @ 5% (percentage by weight of total mix) and lime filler @ 2% (percentage by weight of Aggregate) prepared in Drum Type Hot Mix Plant of 60-90 TPH capacity.

Providing and laying seal coat of premixed fine aggregate (passing 2.36 mm and retained on 180 micron sieve) with bitumen using 128 kg of bitumen of grade VG-10 bitumen per cum of fine aggregate and 0.60 cum of fine aggregate per 100 sqm of road surface including rolling and finishing with road all complete

R Wall: Earth work in excavation by manual means in trenches for foundations, drains, pipes, cables etc. (Not exceeding 1.5 mtr in width & for shafts, wells, cesspits & the like not exceeding 10 sqm on plan, depth upto 1.5 m including disposal of excavated earth upto 1 mtr from cutting edge, disposed earth is to be levelled & neatly dressed. All kinds of soil

Providing & laying in position cement concrete of specified grade excluding the cost of centering and shuttering -- All work upto plinth level 1:5:10 (1 cement : 5 fine sand : 10 graded stone aggregate 40 mm nominal size)

Providing & laying in position cement concrete of specified grade excluding the cost of centering and shuttering -- All work upto plinth level 1:3:6 (1 cement : 3 coarse sand : 6 graded stone agg. 20 mm nominal size) crushed Incl. 20% Plum

Dry Random Rubble masonry with hard stone in foundation & plinth without bond stone

Providing and laying damp-proof Course 50 mm thick with cement concrete 1:2:4 (1 cement:2 coarse sand: 4 graded stone aggregate 20 mm nominal size) and curing complete

Random Rubble masonry with hard stone in foundation and plinth including leveling up with cement concrete 1:6:12 (1 Cement : 6 coarse sand : 12 graded stone aggregate 20mm nominal size) upto plinth level and curing complete with: Cement mortar 1:6 (1 Cement : 6 coarse sand)

Carriage of material by M.T incl. loading/unloading & stacking complete. Sand av lead 50 km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Below 40 mm av lead 20km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone agg. Above 40 mm av lead 20 km

Carriage of material by M.T incl. loading/unloading & stacking complete. Stone av lead 9 km