Check List For RCC Works

Becky July 06, 2013



PILE CAP

  • Remove the laitance from the top of piles before commencing any work.

  • All gaps in the formwork should be filled properly.

  • All sides should be kept in Plumb.

  • Give sufficient supports to the formwork, to avoid the bulging.

  • Concrete Pour Level should be marked on the form work.

  • Provide horizontal support to the column bars above the concrete pour level, to keep the bars in position.

  • Maintain the specified clear cover to the reinforcement (50mm/75mm).

  • Knots and tails of binding wire should not enter into the cover zone.

  • Provide column rings at bottom, middle and top of the pile cap (tie with pile cap stirrups), One master ring to be tied at 4 inch above the concrete top level.

  • Keep the column bars in plumb.

  • Cleaning should be done properly before pouring the concrete.
RAFT AND FOORTINGS

  • Provide end stoppers in raft at the end of the day’s concrete (Construction joint should be vertical)

  • Remove laitance at construction joints before starting next concrete.

  • Maintain top, bottom and side covers in raft and top level should be maintained during finishing of concrete.

  • Binding wire knots and tails should not protrude into cover zone.

  • While casting the footing, concrete at column area also should be vibrated and finished, laitance to be removed at column base after 1 1/2 – 2 hours of finishing the concrete.

  • Column ring at raft top level should be tied with raft top mesh.

  • If possible cast the column starter with footing.
COLUMN STARTER

  • Laitance to be removed from column area.

  • Cleaning should be done before starting concreting.

  • Starter formwork should be made with M.S. sheet or 12 mm ply and wooden planks.

  • Starter height should be of 3 inch or 4 inch (should not be more than 4 inch)

  • Concrete starter should be vibrated properly.
COLUMN / RCC WALL

  • Laitance to be removed from the top of starter before tying any steel for column.

  • Ring must tied One above the other in case of multiple rings.

  • Knots and tails of binding wire should not protrude into cover zone.

  • Provide Chipias (Single legged stirrup/half rings) wherever required.

  • Proper cover must be ensured.

  • Lap bar to be tied 3 inch – 4 inch above the base level.

  • Top link should be 2 inch below the pour level and one master ring must be tied 4 inch above pour level.

  • Only corner lap bars to be joggled.

  • All gaps in the formwork should be filled.

  • Tie bolts in the form work must be horizontal and provide M.S. Washers not less than 2 inch X 2 inch X 6 mm thick. In size to avoid bite in the formwork.

  • Provide Cover stopper (Ghisi Khacha) at the ends and in between spacing not exceeding one meter.

  • Use proper mark level (bharai kanda) to ensure concrete pour level.

  • Column Centerline and Plumb should be checked properly. Wall/column concreting should be done in layers of 45-50 cms and vibrate each layer.

  • While vibrating next layer of concrete needle should immerse 3 inch – 4 inch into Bottom layer of concrete.



SLAB AND BEAMS

  • Beams sides should not be erected unless column top laitance removed and cleaned.

  • Tie Bolts spacing should not exceed 60 cms horizontally. (Sinkayas can be used at bottom to hold beam sides).

  • All gaps in column beam junction and slab must be filled properly and provide half rings (chipias) to column bars in bean depth.

  • All vertical props should be kept in plumb and in line wherever possible. Bracing should be done if slab height is more than nominal height.

  • Proper cover to be maintained in beams, slab and at column-beam junction.

  • All knots and tails of binding wire should not enter into cover zone.

  • Sufficient gap for Vibrator needle should be kept in beams and columns. Beam top and bottom bars more than two nos. tie one below the other using spacer bars of 20 mm or dia. of bar whichever is greater to get sufficient gap of needle.

  • Use proper thickness chairs for bent-up bars in slab. (Ensure top cover)

  • One master ring to column bars is to be tied with slab reinforcement to avoid the displacement for column bars and another master ring at 4 inch above the slab level.

  • Secondary beam bottom steel should rest on the bottom reinforcement of main beam and top bars should go below top bars of main beam.

  • Beam top and bottom bars to be joggled into the column and tied with the column bars.

  • Check the centerline of columns after tying rings at slab level.

SLAB SUPPORTING

  • First prop in beam should be stunt at 9 inch from column.

  • Other props for beam bottom should not be spaced more than 1 foot  9 inch face to face.

  • Any prop should not inclined more than dia. of prop.

  • Joint in props is not allowed.

  • 6 inch X 6 inch X 1 inch thick Wooden plank packing below props to be allowed.

  • More than 2 packing not allowed.

  • Inclined packing must be avoided.

  • Supports/props must be exactly below the ends of acro spans.

  • Stud in beam side should not be more than 1foot 9 inch spaced.

  • All studs must be tied with Tie at top and sinkanja(clamp) at bottom (Tie bolts to be used).

  • External side of beam should be tied with inclined support at top and bottom at 1 foot 9 inch C/C.

  • All column beam junctions to be fixed with stud nut-bolt and yak system.

SLAB

  • Nails for fixing column cap (topy) to be strictly avoided. Use tie bolts or shikanjas(clamp) for fixing column caps.

  • Depth and width of all beams must be checked.

  • Dimensions, diagonal, plumb and supporting of lift pit should be checked properly.

  • Beam bottom should be made with 12 mm ply and wooden planks; simply wooden planks for beam bottom should be avoided.

  • All beam sides should be absolutely in line and plumb.

  • Laitance from top of column and lift pardi(R.C.C. wall) should be removed.

  • Vertacality of elevation must be checked from lower slab elevation.

  • Slab should be absolutely clean.

  • Gaps and gabdi or gap in columns, beam and slab should be strictly avoided.

  • Bearing of beam and slab steel should be checked properly. One master ring of column to be tied with slab steel and check the center line of column to minimize the column steel displacement.

  • Length of bend up bar and lap length should be checked properly.

  • Cover in beam and slab should be 2 foot to 2 foot 6 inches C/C and any steel should not touch beam side or slab shuttering (use of PVC cover blocks is better than the mortar cover blocks made at site)

  • Require dowels to be checked.

  • No binding wire to be used for shuttering.

  • Required dimensions must be properly checked before filling pour card.

Mixer should be in good mechanical condition

·        Gaps between blades should not be more than 1 inch.

·        Direction of blades should be against the direction of rotation of drum.

·  Mixer should be at proper height and level gradation so that chute can be     provided at slope of 45 degree.

·   Water drums 2 nos and water cans 5 ltrs. And 1 ltrs. Should be used to add     water (surface moisture check and correction to be made).

Ø Farmas 30 x 33.3 x 20 to 45, set of six 2 sets to be used for sand CA1 and CA2 (sand bulkage correction to be made).

Ø Country balance should be kept near cement stock and every bag of cement should be weighed (50kg).

Ø Black board giving mix details. (All trial mixer and final mix to be entered)

Ø Half round chute/sliding chute at loading point and unloading point should be of a 45 Degree slope.

Ø Buttering of mixture should be done before taking mix and mixing time should be 1 minute to ½ minute.

Ø Surrounding area should be clean. Partitions should be made for sand, CA1 and CA2 and PCC should be done in material stock area.

Ø Enough material available.


CONCERTING AREA

·        2 Nos vibrators with 40 mm and 60 mm needless should be kept in working conditions. (petrol/kerosene vibrators required in case of power failure)

·        Trolley ghodas(wooden batten) must be used.

·        Walkway ghodas(wooden batten) with planks should be used.

·        Bharai ghodas(wooden batten) must be used to maintain uniform thickness of slab.

·        Electric conduits must be provided (in slabs).

·        Sleeves (if any) should be provided in kitchen sink and in toilets etc., to avoid breaking of beam and slabs for plumbing and other works.

CONCRETING

·        Over all cleaning should be done before concreting.

·        Walk-way Planks to be used while casting the slab.

·        Thickness Ghoda(wooden batten) to be used while concreting so that slab thickness is maintained. Trolley rails should not be laid on slab steel, ghodas(wooden batten)/chairs should be used for trolly rails.

·        Cement Glue(cement water) should be of proper w/c ratio i.e. 0.50.

·        Slab concreting should be done in strips (Bays) to avoid cold joints. Concrete should be placed within 30 minutes for next strip otherwise keep the joint alive by putting one/two pans of concrete at joint and vibrate it.

·        Wooden rammer is required to be used to compact the slab concrete.

·        Cover canda must be placed at working place.

·        Slump cone should be kept one at each mixer and slump should be checked at the beginning and at middle during concreting.

·        Spare Vibrator and needless must be kept ready at the place of concreting.

·        Black Board is to be kept near each mixer and day to day corrections are to be entered and original concrete mix design also should be entered.

·       Wet Hessian Cloth should be layed after finishing the concrete to avoid shrinkage, cracks. If any cracks appeared during concreting finish it immediately using wooden float.

·        Laitance to be removed at column base after 1 ½ -2 hours of finishing the concreting.

Becky

Posted by Becky